Nonoperative Management of Posterior Shoulder Instability: What Are the Long-Term Clinical Outcomes?

OBJECTIVE: To report the injury characteristics, radiographic findings, and long-term outcomes of nonoperative management for posterior shoulder instability (PSI). DESIGN: A retrospective review of 143 patients with PSI using a large geographic database. SETTING: Single county between January 1994 and July 2012. PATIENTS: A clinical history and diagnosis of PSI, one confirmatory imaging study to support the diagnosis, and a minimum of 5 years follow-up were required for inclusion. Patients with seizure disorders, anterior-only instability, multidirectional instability, and superior labrum from anterior to posterior diagnosis were excluded. INTERVENTIONS: Patients with PSI were managed nonoperatively or operatively. MAIN OUTCOME MEASURES: Pain, recurrent instability, and progression into glenohumeral osteoarthritis at long-term follow-up. RESULTS: One hundred fifteen patients were identified. Thirty-seven (32%) underwent nonoperative management. Twenty (54%) patients were diagnosed with posterior subluxation, 3 (8%) with a single dislocation, and 7 (19%) with multiple dislocations. Symptomatic progression of glenohumeral arthritis was observed in 8% (3) of patients. Pain improved in 46% (17) of patients and worsened in 19% (7). Recurrent instability and progression to osteoarthritis occurred in 15% (3/20) of patients with a traumatic instability event compared with 0% of atraumatic patients after nonoperative management (P = 0.234). Pain at follow-up was more common in nonoperative than operative patients (P = 0.017). CONCLUSIONS: Nonoperative management is a viable option for many patients with posterior shoulder instability; however, many may continue to have posterior shoulder pain.

Multiple Instability Events at Initial Presentation Are the Major Predictor of Failure of Nonoperative Treatment for Anterior Shoulder Instability.

PURPOSE: To define the success rate of initial nonoperative treatment for traumatic anterior shoulder instability in a defined U.S. geographic population, describe factors that predict conversion to surgery after initial nonoperative management, and describe the long-term outcomes of nonoperative treatment after the index traumatic anterior instability event. METHODS: The Rochester Epidemiology Project database was used to identify patients aged 14 to 39 years treated for anterior shoulder instability between 1994 and 2016. Patient demographic characteristics, comorbidities, injury characteristics, and imaging were evaluated. Patients treated nonoperatively for the first 6 months after the index instability event were analyzed to determine long-term outcomes (recurrence rate, pain at last follow-up, radiographic outcomes), the success rate of continued nonoperative treatment (no conversion to surgery), and factors associated with conversion to surgery (patient and injury characteristics). Survivorship free of surgery was reported with a Kaplan-Meier survival curve, and Cox proportional hazards models were used to evaluate association of variables with conversion to surgery. RESULTS: A total of 379 patients met the study criteria, with an average follow-up period of 10.2 years (range, 0.53-25.00 years). The average age was 23.9 years, the mean body mass index was 26.2, and 100% of instability events were due to trauma. Of the shoulders, 79 (20.1%) ultimately failed initial nonoperative treatment and progressed to surgery. At final follow-up, the rate of recurrent instability was 52.3% in the group treated definitively without surgery, and the recurrence rate decreased from 92.4% to 10.1% in patients who underwent conversion to surgical treatment. Factors associated with conversion to surgery included 2 or more subluxations prior to the first evaluation (hazard ratio [HR], 1.82; P = .002), 2 or more dislocations prior to the first evaluation (HR, 1.76; P = .006), and recurrent instability at follow-up (HR, 4.21; P < .001). CONCLUSIONS: Most patients younger than 40 years with shoulder instability who were initially treated nonoperatively for 6 months were definitively treated without surgery. Ultimately, 35% of these patients experienced recurrent dislocations after 6 months of conservative treatment and 20% underwent surgical treatment. In most patients who underwent conversion to surgical treatment, surgery was performed within 12.5 years of their first instability event. Patients who experienced multiple instability events before or after consultation were more likely to undergo conversion to surgery after initial nonoperative management. LEVEL OF EVIDENCE: Level III, retrospective database review.

Pre-operative patella alta does not affect midterm clinical outcomes and survivorship of patellofemoral arthroplasty.

PURPOSE: The purpose of this study was to evaluate the effect of preoperative patella alta on clinical outcomes, survivorship, and complication and reoperation rates on patellofemoral arthroplasty (PFA). METHODS: All patients who underwent PFA for isolated patellofemoral arthritis by a single surgeon at our institution were identified. Preoperative radiographs were measured by two independent observers for patellar height using the Caton Deschamps (CD), Insall-Salvati (IS), and Blackburne-Peele (BP) methods. Patients were classified as either "patella alta" or "non-patella alta" for all three measurement methods. Clinical scores including KSS Pain, KSS Function, and Tegner Activity Scores were collected pre- and post-operatively. Failure was defined as conversion to total knee arthroplasty (TKA). Clinical outcomes and survivorship were compared between patients with "patella alta" and "non-patella alta" height measurements. RESULTS: There were 119 patients with 153 knees (86% female) included in the study with a mean age of 55.8 years. Outcome scores improved from pre-operative to post-operative for both patella alta and non-patella alta patients for Tegner, KSS pain and KSS function scores. The mean change in Tegner scores for patella alta and non-patella alta patients were not significantly different for CD (p = 0.24), IS (p = 0.25) or BP measurements (p = 0.39). The mean change in KSS pain scores between groups were not significantly different for CD (p = 0.33) or IS measurements (p = 0.22), but was improved more significantly in patella alta patients vs non-patella alta patients (21.2 and 14.4; p = 0.02) for BP measurement. The mean change in KSS function scores between groups was not significantly different for CD (p = 0.61) IS (p = 0.90) or BP measurements (p = 0.79). The overall survivorship from conversion to total knee arthroplasty (TKA) was 94.1% at a mean follow-up time of 5.0 (SD 2.6) years. There were no significant differences in survivorship from TKA between patella alta and non-patella alta groups (CD: p = 0.72, IS: p = 0.63, BP: p = 0.66). CONCLUSIONS: This study suggests that there are no significant differences in clinical outcome scores or survivorship from TKA between patella alta and non-patella alta patients who underwent onlay design PFA. Both patella alta and non-patella alta patients demonstrated excellent improvement in outcome scores from pre-operative to post-operative. LEVEL OF EVIDENCE: IV.

Comparable clinical outcomes using knotless and knot-tying anchors for arthroscopic capsulolabral repair in recurrent anterior glenohumeral instability at mean 5-year follow-up.

PURPOSE: To compare rates of recurrent instability, revision surgery and functional outcomes following arthroscopic anterior capsulolabral repair for recurrent anterior instability using knot-tying versus knotless suture anchor techniques. METHODS:  Patients who had undergone arthroscopic anterior labrum and capsular repair for recurrent anterior glenohumeral instability using knotless anchors were identified. Those with minimum 2-year follow-up were matched (1:2) to knot-tying anchor repair patients. Rates of failure and recurrent instability were compared, as well as Visual Analog Scale (VAS), Single Assessment Numeric Evaluation (SANE), Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH), University of California Los Angeles (UCLA) and Rowe scores. RESULTS: One hundred and two patients (89 males, 13 females) with a mean age of 24.3 ± 9.6 were included. Repair was performed with knotless anchors in 34 and knot-tying anchors in 68 shoulders. At mean follow-up of 4.8 ± 2.5 years, re-dislocation rates between groups were not significantly different (knotless anchor: 9% versus knot-tying group: 15%, n.s.), but the knot-tying group showed a higher re-subluxation rate (p = 0.039). 12 (18%) revisions were performed in the knot-tying group at a mean 2.9 years after surgery and 1 (3%) revision in the knotless anchors group at 1.4 years (n.s.). There was no difference in mean VAS with use (1.3 ± 1.9 versus 0.8 ± 1.5, n.s.), SANE scores (91.8 ± 12.7 versus 92.0 ± 11.0, n.s.), QuickDASH scores (4.1 ± 5.5 versus 3.0 ± 6.5, n.s.), UCLA Shoulder Score (32.5 ± 3.6 versus 33.2 ± 3.1, n.s.), or Rowe scores (90.5 ± 18.5 versus 92.2 ± 16.6, n.s.) between knotless and knot-tying groups, respectively. VAS at rest was higher in the knotless group (0.7 ± 1.5 vs 0.1 ± 0.4, p = 0.021). CONCLUSIONS: Knotless anchors demonstrated similar rates of re-dislocation and revision surgery, and lower rates of recurrent subluxation, compared to knot-tying anchors. Patients achieved good-to-excellent functional outcomes. This supports the efficacy of knotless anchors as an alternative to knot-tying anchors for arthroscopic anterior labral repair of recurrent anterior shoulder dislocation. LEVEL OF EVIDENCE: III.

Smoking, unemployment, female sex, obesity, and medication use yield worse outcomes in patellofemoral arthroplasty.

PURPOSE: The purpose of this study was to identify effects of psychosocial and demographic factors on patellofemoral arthroplasty (PFA) outcomes. METHODS: Patients who underwent PFA by a single surgeon between 2002 and 2013 (min. 2 year follow-up) were included. Knee Society scores (KSS), UCLA, and Tegner Scores were prospectively collected in a designated arthroplasty registry. Patient records were retrospectively reviewed and univariate and multivariate statistical analyses were performed to assess the effect of psychosocial factors and demographic variables including patient sex, BMI, smoking and medication use, psychiatric history, and employment status on improvement between pre- and post-operative scores. RESULTS: Seventy-four knees in 55 patients (88% female) with a mean age of 51.8 (SD 8.8) and mean follow-up of 46.5 (SD 26.9) months were included. Patients showed significant improvement in all functional outcomes (p < 0.001). Mean improvement in KSS-F scores and median improvement in Tegner scores was greater in males compared to females (37.8 vs 16.1, p = 0.007; 3.0 vs 2.0, p = 0.07, respectively). Smokers showed less improvement in KSS-P compared to non-smokers (17.2 vs 30.0, p = 0.028). Retired or employed patients had a greater mean improvement in KSS-F and median improvement in Tegner Scores compared to those were unemployed or on work disability (p = 0.022, p = 0.01). Patients who reported using opioids and/or anti-depressants pre-operatively showed less improvement in UCLA scores (p = 0.006). Obese patients showed less improvement in both KSS-F and Tegner score compared to non-obese patients (p = 0.009, p = 0.004). CONCLUSION: Psychosocial factors influence the degree of improvement following PFA. Although patients showed overall improvement compared to their baseline scores, obese patients, smokers, unemployed/work disabled, and pre-operative use of opioids and/or anti-depressants were risk factors for decreased improvement… The consideration of psychosocial variables are clinically important when assessing a patient's candidacy for PFA and improve pre-operative patient selection and counselling. LEVEL OF EVIDENCE: Level IV.

The Recurrent Instability of the Patella Score: A Statistically Based Model for Prediction of Long-Term Recurrence Risk After First-Time Dislocation.

PURPOSE: To describe the clinical history of a series of primary, lateral patellar dislocations and determine long-term predictors of recurrent instability while accounting for patients undergoing early operative management. METHODS: A large geographic database of more than 500,000 patients was used to identify patients who sustained a first-time lateral patellar dislocation between 1990 and 2010. Charts were individually reviewed to document demographics, radiographic measures including tibial tubercle to trochlear groove distance (TT-TG) and patellar length (PL), recurrent episodes of instability, and patellar stabilization surgery. A risk score that accounted for early surgical management was calculated using Fine and Gray competing risk regression, and its ability to stratify patients was examined using cumulative incidence curves. RESULTS: Eighty-one patients (mean age 19.9 ± 9.4 years, 38 male, 43 female) were identified and followed for a mean of 10.1 years (range 4.1-20.2). Thirty-eight patients (46.9%) experienced an episode of recurrent instability and 30 (37.0%) underwent patellar stabilization surgery, including 7 who did so before recurrent dislocation. A multivariate, statistically derived scoring system, the Recurrent Instability of the Patella Score (RIP Score), that employed age, skeletal maturity, trochlear dysplasia, and TT-TG/PL ratio to predict recurrent instability while accounting for patients managed surgically, was generated. The resulting RIP score stratified patients into low-, intermediate-, and high-risk categories, with 0.0%, 30.6%, and 79.2% 10-year recurrent instability rates, respectively (P = .000004), and an area under the curve of 0.875 (P = .00002). CONCLUSIONS: Patients who sustain a first-time, lateral patellar dislocation can be readily classified into low-, intermediate-, and high-risk categories employing the RIP score based on age, skeletal maturity, trochlear dysplasia, and TT-TG/PL ratio. This long-term risk stratification holds significant potential clinical utility for determination of patients who are at high risk for recurrent instability after primary patellar dislocation. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Nonoperative Management of Posterior Shoulder Instability: An Assessment of Survival and Predictors for Conversion to Surgery at 1 to 10 Years After Diagnosis.

PURPOSE: To (1) define the rate of delayed surgery, between 1 and 10 years after injury, in a population-based study of patients with posterior shoulder instability (PSI), (2) evaluate predictive factors associated with delayed repair, and (3) identify differences between the nonoperative and operative groups at long-term follow-up. METHODS: A population-based retrospectively reviewed study of all patients with PSI from January 1, 1994, to December 31, 2015, was performed. Inclusion required a clinical diagnosis of PSI combined with supporting imaging. Complete medical records were reviewed for 2,091 potential cases. Kaplan-Meier estimates were used to calculate survival. Landmark survival analysis was performed to identify predictors of conversion to surgery. RESULTS: The study included 143 patients with PSI, 79 of whom were managed nonoperatively for at least 1 year after diagnosis. After the first year, survival free of surgery was 78.3% at 1 year, 63.1% at 5 years, and 51.5% at 10 years. There was a trend toward increased surgery in patients with a body mass index > 35 (P = .10; hazard ratio = 2.32; confidence interval, 0.8-6.8). Nonthrowing athletes (including contact/weight-lifting athletes) showed a trend toward an increased risk for surgery (P = .07). Patients who underwent surgery were significantly more likely to have progression in arthritis (P = .02; hazard ratio = 4.0; confidence interval, 1.2-13.2). CONCLUSIONS: Nonoperative management was performed for at least 1 year in over half of patients diagnosed with PSI. Overall, long-term follow-up demonstrates that 46% of these patients converted to surgery between 1 and 10 years after initial diagnosis. Ultimately, 70% of patients diagnosed with PSI go on to surgical intervention. Patients who underwent surgery at any time point were at an increased risk of radiographic progression of arthritis at a minimum of 5 years of follow-up. LEVEL OF EVIDENCE: Level III, cohort study.

Systematic Review of Medial Patellofemoral Ligament Reconstruction Techniques: Comparison of Patellar Bone Socket and Cortical Surface Fixation Techniques.

PURPOSE: To compare patellar bone socket and cortical surface fixation techniques for isolated medial patellofemoral ligament (MPFL) reconstruction and determine whether there was a difference in (1) complication rates, including fracture of the patella; (2) redislocation rates; or (3) patient-reported outcomes. METHODS: A literature search was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We included patients who underwent isolated MPFL reconstruction for recurrent patellar instability. Patients with confirmed concomitant or prior ipsilateral knee procedures, multiligament injury, or less than 3 months of follow-up were excluded. Risk-of-bias assessment was performed using the Methodological Index for Non-randomized Studies (MINORS) system. Studies were classified by surgical technique (patellar bone socket group [group S] vs cortical fixation group [group F]), and complications, redislocations, and patient-reported outcomes were collected. RESULTS: A total of 29 studies yielded 981 patients with MPFL reconstruction for inclusion. Of the patients, 620 underwent a patellar bone socket technique and 361 underwent a cortical fixation technique. Patients ranged in age from 11 to 68 years. Patellar fracture rates ranged from 0% to 17% in group S and were 0% in all group F studies. Mean Kujala scores ranged from 83.5 to 93.6 in group S and from 84.4 to 94.5 in group F. Mean Lysholm scores ranged from 84.6 to 91.7 in group S and from 83.5 to 95 in group F. Redislocation rates ranged from 0% to 21% in group S and from 0% to 13% in group F. Although heterogeneous in nature, complication rates ranged from 0% to 28% in group S and from 0% to 4% in group F. CONCLUSIONS: MPFL reconstruction techniques with patellar bone sockets showed a larger range of complication rates than cortical fixation techniques, although overall, complications remained uncommon. Clinically, the bone socket group had comparable postoperative redislocation rates and patient outcomes to the group treated with cortical fixation techniques. LEVEL OF EVIDENCE: Level IV, systematic review of Level I through IV studies.

Incidence of posterior shoulder instability and trends in surgical reconstruction: a 22-year population-based study.

BACKGROUND: The incidence of posterior shoulder instability (PSI) in the general population is not well defined. This study aimed to define the population-based incidence of PSI and describe trends in incidence and surgery rates. METHODS: The study population included 143 patients (16 females, 127 males) diagnosed with new-onset PSI between January 1, 1994, and December 31, 2015. Medical records were reviewed to extract patient data. Age- and sex-specific incidence rates were calculated and adjusted to the 2010 United States population. Poisson regression was performed to examine trends by timeline, sex, and age. RESULTS: Age- and sex- adjusted annual incidence of PSI was 4.64 per 100,000 person-years, and posterior dislocation was 1.30 per 100,000 person-years. Peak PSI incidence for males and females was at 14 to 19 years (31.82 and 5.23 per 100,000 person-years). PSI incidence was higher in males than females (8.86 vs. 1.07 per 100,000 person-years, P < .001). The 5-year cumulative risk of surgery for patients with PSI was 53.1% between 1996 and 2002, 59.9% between 2003 and 2008, and 87.5% between 2009 and 2015. Patients with PSI between 2009 and 2015 had a significantly increased rate of surgery (hazard ratio, 2.2; 95% confidence interval, 1.4-3.6; P = .001) compared with those between 1996 and 2002. CONCLUSION: The age- and sex- adjusted incidence of PSI in the general population was 4.64 per 100,000 person-years. There is a significantly greater incidence of PSI in males than females, with both sexes peaking at 14 to 19 years and incidence rates remaining elevated throughout the third and fourth decades of life. The incidence of PSI remained stable over time; however, the rate of surgical intervention increased significantly, from 53.1% of patients between 1996 and 2002 to 87.5% of patients between 2009 and 2015.

Combined Tibial Tubercle Osteotomy and Medial Patellofemoral Ligament Reconstruction for Recurrent Lateral Patellar Instability in Patients With Multiple Anatomic Risk Factors.

PURPOSE: To report the outcomes for combined tibial tubercle osteotomy (TTO) and medial patellofemoral ligament (MPFL) reconstruction and assess for potential risk factors for recurrent instability and/or poor outcomes. METHODS: The medical record at our institution was reviewed for patients treated with MPFL reconstruction and TTO for recurrent lateral patellar instability from 1998 to 2014. Preoperative imaging was assessed for trochlear dysplasia according to the Dejour classification (high grade = B, C, D) and the presence of patella alta using the Caton-Deschamps ratio (>1.2). The indication for combined MPFL reconstruction and TTO was MPFL insufficiency and a lateralized tibial tubercle. Outcomes were determined by recurrent instability, return to sport, and Kujala and International Knee Documentation Committee (IKDC) scores. RESULTS: Thirty knees in 28 patients (14 M, 14 F) with a mean age of 22.6 ± 9.1 years (range, 13-51 years) were included with a mean follow-up of 48 ± 28 months (24-123 months). Seventy-three percent (22/30) had high-grade trochlear dysplasia, and 63% (19/30) had patella alta. One patient had a postoperative dislocation and 1 had a subluxation event. The Caton-Deschamps ratio decreased by a mean of 0.2 (P = .001), leaving 30% with postoperative patella alta. The mean postoperative scores were as follows: Tegner = 5 ± 2, Kujala = 89 ± 16 (45-100), and IKDC = 85 ± 17 (44-100). Eighty-three percent (15/18) returned to their preoperative sport. Female gender was a risk factor for lower IKDC (77.3 vs. 92.6, P = .01) and Kujala (82.2 vs. 95.0, P = .03) scores. Medialization greater than 10 mm was directly correlated to lower IKDC (P = .02) and Kujala (P = .01) scores. CONCLUSIONS: The combination of MPFL reconstruction and TTO in patients with trochlear dysplasia results in low recurrence of instability. Patients on average had good subjective outcomes and were able to return to sport. Female gender and tibial tubercle medialization greater than 10 mm were associated with worse outcomes. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

High rate of recurrent patellar dislocation in skeletally immature patients: a long-term population-based study.

PURPOSE: Patellar dislocation can occur in isolation or be associated with chronic instability. The goals of this study are to describe the rate and factors associated with additional patellar instability events (ipsilateral recurrence and contralateral dislocation), as well as the development of patellofemoral arthritis in patients who are skeletally immature at the time of first patellar dislocation. METHODS: The study included a population-based cohort of 232 skeletally immature patients who experienced a first-time lateral patellar dislocation between 1990 and 2010. A chart review was performed to collect information related to the initial injury, treatment, and outcomes. Subjects were followed for a mean of 12.1 years to determine the rate of subsequent patellar dislocation (ipsilateral recurrence or contralateral dislocation) as well as clinically significant patellofemoral arthritis. RESULTS: 104 patients had ipsilateral recurrent patellar dislocation. The cumulative incidence of recurrent dislocation was 11% at 1 year, 21.1% at 2 years, 37.0% at 5 years, 45.1% at 10 years, 54.0% at 15 years, and 54.0% at 20 years. Patella alta (HR 10.6, 95% CI 3.6, 36.1), TT-TG ≥ 20 mm (HR 18.7, 95% CI 1.7, 228.2), and trochlear dysplasia (HR 23.7, 95% CI 1.0, 105.2) were associated with recurrence. Similarly, 18 patients (7.8%) had contralateral patellar dislocation. The cumulative incidence of patellofemoral arthritis was 0% at 2 years, 1.0% at 5 years, 2.0% at 10 years, 10.1% at 15 years, 17% at 20 years, and 39.0% at 25 years. Osteochondral injury was associated with arthritis (HR 25.7, 95% CI 6.2, 143.8). There was no association with trochler dysplasia (HR 1.2, 95% CI 0.2, 5.0), recurrent patellar instability (HR 1.2, 95% CI 0.2, 7.2), gender (HR 1.3, 95% CI 0.3, 5.6), or patellar-stabilizing surgery (HR 0.7, 95% CI 0.2, 3.5) and arthritis. CONCLUSION: Skeletally immature patients had a high rate of recurrent patellar instability that was associated with structural abnormalities such as patella alta,TT-TG ≥ 20 mm, and trochlear dysplasia. Approximately 10% of patients experienced a contralateral dislocation and 20% of patients developed arthritis by 20 years following initial dislocation. Osteochondral injury was associated with arthritis. LEVEL OF EVIDENCE: Retrospective case series, Level IV.

Partial meniscectomy provides no benefit for symptomatic degenerative medial meniscus posterior root tears.

PURPOSE: Medial meniscus posterior root tears (MMPRTs) are recognized as a source of pain and dysfunction, but treatment options remain a challenge. The purpose of the study was to determine (1) the efficacy of partial meniscectomy to treat MMPRTs compared to a matched group of non-operatively treated MMPRTs, and (2) risk factors for worse clinical and radiographic outcome. METHODS: This retrospective comparative study was performed to include patients with complete, isolated MMPRTs with documented clinical symptoms and were treated with arthroscopic partial meniscectomy (PMM) and a minimum 2-year follow-up. These patients were then matched by age, gender, and BMI to patients with the same diagnosis who were treated non-operatively. Clinical and radiographic outcomes were compared between the two groups. Analysis was performed to determine risk factors for worse clinical and radiographic outcome in the PMM group alone. RESULTS: Overall, 52 patients were included in the study. Twenty-six patients (9M:17F) with a mean age of 55 ± 9 and a mean BMI of 32.8 ± 5.3 were treated with PMM and followed for 5.5 ± 2.0 years (range 2.3-9.3 years). In the PMM group, final median Tegner score was 3, mean IKDC score was 67.8 ± 20, and more patients had grade II or higher arthritis at final follow-up than baseline (91.3 vs. 36%, p < 0.01). Overall, 14 of the 26 patients (54%) treated operatively progressed to total knee arthroplasty at a mean of 54.3 months. There was no significant difference in final Tegner scores, IKDC, K-L grades, progression to arthroplasty, or overall failure rate between the PMM group and non-operative group. Following PMM, female patients had lower final IKDC scores (44.0 ± 2.8 vs. 74.6 ± 16.7, p = 0.02) compared to males, as well as a higher rate of arthroplasty (70.6 vs. 20.0%, p = 0.009). Higher BMI correlated with lower IKDC scores (r = -0.91, p = 0.01) and meniscal extrusion was associated with higher rate of arthritis at final follow-up (p = 0.02). CONCLUSION: Partial meniscectomy for a complete MMPRT provides no benefit in halting arthritic progression. Patients who undergo PMM for MMPRTs still progress to significant arthritis, poor clinical outcomes and a high arthroplasty rate (54%) at over 5-year follow-up. Female gender, increased BMI, and meniscus extrusion were associated with worse outcome. STUDY DESIGN: Level III.

Short- to mid-term outcomes of anatomic MCL reconstruction with Achilles tendon allograft after multiligament knee injury.

PURPOSE: Multiple techniques have been described in the literature for reconstruction of the medial collateral ligament. The purpose of this study is to describe functional outcome, range of motion, and knee stability following anatomic MCL reconstruction utilizing an Achilles tendon bone allograft after multiligament knee injury. METHODS: A comprehensive search of a single-hospital multiligament knee injury (MLKI) procedural database was conducted to identify all patients that underwent reconstruction of the MCL utilizing an Achilles tendon bone allograft and with 2-year clinical follow-up. Medical charts were retrospectively reviewed to determine each patient's knee dislocation (KD) grade, final range of motion, stability on clinical examination, and the incidence of complications and reoperations. KOOS, IKDC, and Marx scores were also collected. RESULTS: Thirty-two knees in 32 patients (21 males and 11 females) with a mean age of 30 years (range 15-51) were followed for an average of 40 months (range 28-87 months) following MCL reconstruction with Achilles tendon bone allograft. For patients with multiligament knee injuries, there were 14 KD-I (11 ACL/MCL; 3 MCL/PCL; 1 MCL/ACL/LCL; 1 MCL/PCL/LCL), 12 KD 3-M, and 3 KD-IV. One patient underwent isolated revision MCL reconstruction. At final follow-up, clinically significant valgus laxity was observed in only 1 patient (3%). All patients were able to achieve full extension of the knee and the average flexion was 121.1 ± 19.6. The average IKDC score was 67.6 ± 19.9 (range 27.7-98.9), the average KOOS score 77.1 ± 16.8 (range 31-100). The average Marx score was 4.9 (range 0-16, SD 5.2). Thirty-one of 32 (96%) patients reported being satisfied with results of the surgery. Knee dislocation grades were significantly correlated with post-operative outcome measures. CONCLUSION: In a series utilizing a modified Marx Achilles tendon, MCL reconstruction in the setting of MLKI demonstrated satisfactory clinical and functional outcomes, as well as patient satisfaction at short- to mid-term follow-up. Furthermore, knee dislocation grades were demonstrated to correlate with post-operative IKDC, KOOS, and Marx scores. LEVEL OF EVIDENCE: Type IV.

Functional testing and return to sport following stabilization surgery for recurrent lateral patellar instability in competitive athletes.

PURPOSE: Medial patellofemoral ligament (MPFL) reconstruction and tibial tubercle osteotomy are commonly used to treat recurrent lateral patellar instability, yet there are limited available data on return to sport (RTS) following these procedures. The purpose of this study is to evaluate patient factors associated with excellent functional outcomes, including successful RTS, following surgical stabilization including MPFL reconstruction in competitive athletes with recurrent lateral patellar instability. METHODS: Athletes undergoing primary MPFL reconstruction for recurrent lateral instability from 2005 to 2013 were identified at a single institution. Concomitant procedures, such as tibial tubercle osteotomy (TTO), were included. Patient demographic information, including BMI, gender, age, and pre-injury Tegner score, was recorded. In addition, radiographs were reviewed for pre-operative patellar height (Caton-Deschamps index) and trochlear dysplasia (Dejour classification). All patients underwent a standardized rehabilitation/post-operative protocol, with isokinetic strength and functional testing being performed at 6 months post-operatively. Final Tegner scores, RTS status, subjective instability ratings, and Kujala scores were collected at a minimum of 2 years. Chi-squared analysis for categorical variables and Wilcoxon rank-sum analysis for continuous variables were used to determine the relationship between the previously mentioned patient and knee characteristics with isokinetic data, RTS status, or Kujala scores. RESULTS: Thirty-nine athletes (23 male, 16 female) at a mean age of 17.5 ± 2.9 years (range, 13-26) underwent primary MPFL reconstruction (32 autografts, seven allografts) for recurrent patellar instability with a mean follow-up of 47.0 ± 16.4 months. Sixteen patients (41%) underwent concomitant tibial tubercle osteotomies. Isokinetic data collected at 6 months post-operatively demonstrated mean knee flexion and extension strength deficits of 15.8 ± 10.1% and 21.4 ± 14.3%, respectively, compared to the contralateral leg (p < 0.001 for both). Patients who underwent concomitant tibial tubercle osteotomy (p = 0.04), males (p = 0.01) and those with patella alta (p = 0.04) had weaker 6-month isokinetic testing. Thirty-three of the thirty-nine (85%) athletes were able to RTS at a mean of 8.1 ± 3.9 months. Patients undergoing MPFL with concomitant TTO (p = 0.02) returned to sport at a slower rate. One patient (3%) reported an episode of recurrent dislocation requiring revision surgery. Kujala and Tegner scores at final follow-up were 91.1 ± 6.3 and 6 (range, 4-9), respectively. CONCLUSION: Surgical stabilization including MFPL reconstruction for recurrent lateral patellar instability is an effective procedure for returning athletes to competitive sports. However, strength deficits persist at 6 months after surgery, especially in those undergoing concomitant TTO, which may delay return to sport. Physicians can use these results to counsel patients that return to competitive sports is safe with good clinical outcomes and low rate of recurrence at 4-year follow-up; however, predisposing factors, like a lateralized tibial tubercle, should be addressed if necessary, but athletes should be counselled that a slower recovery and longer return to sport time may be expected. LEVEL OF EVIDENCE: IV.

Individualizing the tibial tubercle to trochlear groove distance to patient specific anatomy improves sensitivity for recurrent instability.

PURPOSE: An initial episode of patellar instability poses a treatment challenge given the absence of a valid, reproducible, and universally applicable predictor of recurrence. Recently, a series of patellar instability ratios (PIRs) were described. Each ratio consisted of the traditional tibial tubercle to trochlear groove (TT-TG) distance normalized to patient-specific measures. The purpose of this study was to investigate the reliability and validity of these novel measures. METHODS: Eighty-seven patients experiencing a first-time lateral patellar dislocation were identified in a retrospective manner. Magnetic resonance imaging (MRI) studies obtained at the time of injury were reviewed. The TT-TG distance, patellar width (PW), trochlear width (TW), patellar length (PL), and trochlear length (TL) were obtained by two observers in a blinded, randomized fashion. Measurement reliability was assessed using intra-class correlation coefficients (ICCs). Patients were divided into those having a single dislocation (Group 1) and those experiencing recurrent instability (Group 2). The ability of the TT-TG distance and each PIR to predict recurrent instability was assessed by calculating odds ratios (ORs) with 95% confidence intervals (CIs). Sensitivity and specificity were also calculated for each measure. RESULTS: Excellent inter-rater agreement was observed with ICCs > 0.75 for all patellofemoral joint measurements obtained on MRI. The TT-TG distance alone was predictive of recurrent patellar instability with an OR of 8.9 (p < 0.001). However, the isolated TT-TG distance had the lowest sensitivity at 25.6%. Among ratios, a TT-TG/PL ≥ 0.5 was the most predictive of recurrent instability with an ORs of 6.1 (p = < 0.001). A TT-TG/TL ≥ 0.8 was also predictive of recurrence (OR 4.9, p = 0.027) and had the highest sensitivity of any measure at 94.9%. CONCLUSION: The results of the current study support the reproducibility and predictive ability of PIRs. While a TT-TG ≥ 20 mm was the strongest predictor of recurrent patellar instability, it was a relatively insensitive measure. Sensitivity may be improved by normalizing the TT-TG distance to patient-specific axial and sagittal plane patellofemoral measurements on MRI. Ultimately, PIRs are reproducible measures that may serve as an additional tool when clinically assessing the unstable patellofemoral joint. LEVEL OF EVIDENCE: III.

Increased Risk of Revision, Reoperation, and Implant Constraint in TKA After Multiligament Knee Surgery.

BACKGROUND: The risk of major complications and revision arthroplasty after TKA in patients who previously underwent multiligament knee surgery have been poorly characterized. QUESTIONS/PURPOSES: Is multiligament knee surgery before TKA associated with (1) worse implant survival, (2) increased use of TKA design constraint, (3) a greater risk for major complications, and (4) poorer scores for pain and function compared with similar patients receiving TKA for primary osteoarthritis? METHODS: Fifty-nine TKAs were performed at our institution between 1985 and 2014 in 59 patients (36 men, 23 women; mean age, 53 years) with a history of previous multiligament knee surgery (≥ two ligaments). Of those, we had followup for 39 (66%), 18 (31%), and six (10%) patients at 5, 10, and 15 years, respectively; mean followup was 5.4 years (range, 1-25 years). A two-to-one matched control group consisting of patients undergoing primary TKA for the diagnosis of osteoarthritis was selected for comparison. Patients were matched based on gender, age at primary TKA (within 5 years), and date of the TKA (within 5 years). Medical records were reviewed for survivorship, TKA design, complications (reoperation, revision, infection, manipulation under anesthesia, and periprosthetic joint infection), TKA design, and clinical outcomes (Knee Society Scores [KSS], Knee Society Function Score [KSS-F]). RESULTS: The overall 15-year revision-free survival in patients with prior multiligament knee surgery was decreased in comparison to the matched controls (42% [95% CI, 16%-73%] vs 94% [95% CI, 81%-99%]; p < 0.001). Varus-valgus constraint implant design was used for more patients in the multiligament cohort at index TKA than in the matched control group (9/59 [15%] vs 0/110 [0%], respectively; odds ratio [OR], 45; 95% CI, 3-781; p = 0.009). Patients with a history of multiligament knee surgery also were at increased risk of reoperation for any cause (14/59 [24%] vs 7/118 [6%]; OR, 5; 95% CI, 2-14; p = 0.001). With the numbers available, there was no difference in the frequency of manipulation under anesthesia after TKA (10% [6/59] versus 3% [4/118]; p = 0.08) A higher proportion of patients in the multiligament cohort had infections develop compared with the matched controls (4/59 [7%] vs 1/118 [< 1%)], respectively; p = 0.04). There was no difference in the KSS improvement after TKA between the multiligament group and the control group (34 ± 18 vs 28 ± 15; p = 0.088). The final KSS and KSS-F scores likewise showed no difference between those groups (88 ± 13 vs 85 ± 10; p = 0.232) (85 ± 17 vs 84 ± 14; p = 0.75). CONCLUSIONS: A history of multiligament surgery is associated with lower long-term survivorship, higher use of constrained TKA designs, and higher risk of major complications, including reoperation and infection. Further research is necessary to determine if a particular multiligamentous surgical technique can prevent posttraumatic arthritis and TKA complications. LEVEL OF EVIDENCE: Level III, therapeutic study.

Management of Patellofemoral Arthritis: From Cartilage Restoration to Arthroplasty.

The management of patellofemoral cartilage lesions is controversial and should begin with a comprehensive nonsurgical treatment plan. Patients with patellofemoral cartilage lesions in whom nonsurgical treatment fails may be candidates for surgical treatment. Surgical treatment strategies for the management of patellofemoral cartilage lesions are guided by the size, quality, and location of the defect. Recent advancements in cartilage restoration and arthroplasty techniques as well as appropriate patient selection and meticulous surgical technique have resulted in promising outcomes for patients with patellofemoral cartilage lesions who undergo surgical treatment.

Return to sport: Does excellent 6-month strength and function following ACL reconstruction predict midterm outcomes?

PURPOSE: The purpose of this study was to determine whether patients with excellent 6-month functional testing after ACL reconstruction had (1) higher risk of subsequent ACL tears, (2) superior knee function, and (3) increased activity levels compared to those with delayed clearance for return to sports at midterm follow-up. METHODS: A total of 223 patients underwent primary ACL reconstruction by a single surgeon and had functional and isokinetic testing performed 6 months post-operatively between 1998 and 2005. Of the 223 patients, 52 (23 %) made the excellent group and were allowed return to sport at 6 months, and the remaining 171 (77 %) constituted the delayed group. Rate of ACL graft tear and native contralateral ACL tear was compared between groups. In addition, IKDC and Tegner scores were compared at a mean 4-year follow-up. RESULTS: The graft rupture rate was similar in the excellent group (3.8 %, n = 2) compared to the delayed group (4.7 %, n = 8; p = 0.30). However, there was a higher rate of contralateral ACL tear in the excellent group (15.4 %, n = 8 vs. 5.3 %, n = 9; p = 0.003). The excellent 6-month group had superior IKDC scores (94.3 ± 6.4 vs. 90.9 ± 9.7; p = 0.04) and Tegner scores (6.6 ± 1.8 vs. 5.7 ± 1.6; p = 0.01). CONCLUSION: Patients with an excellent performance on their isokinetic strength and functional testing at 6 months after ACL reconstruction have superior knee function and higher activity levels at midterm follow-up. However, these patients appear to be at greater risk of contralateral ACL injury, which may be related to their increased activity level. When isokinetic and functional testing is used for return-to-sport decisions, physicians should caution patients about the risk of contralateral ACL injury for high performing patients. LEVEL OF EVIDENCE: Retrospective Review with Control, Level III.

The contribution of the tibial tubercle to patellar instability: analysis of tibial tubercle-trochlear groove (TT-TG) and tibial tubercle-posterior cruciate ligament (TT-PCL) distances.

PURPOSE: The purpose of this study is to assess the reliability of measuring the tibial tubercle to posterior cruciate (TT-PCL) distance compared to the tibial tubercle to trochlear groove (TT-TG) distance on magnetic resonance imaging (MRI), establish baseline TT-PCL values in patellar instability patients, and determine the predictive value of an excessive TT-PCL distance (≥24 mm) for recurrent patellar instability compared to a TT-TG distance ≥20 mm. METHODS: TT-TG and TT-PCL distances were calculated on MRI in a randomized and blinded fashion by two reviewers on 54 patients (59 knees) with patellar instability. Interobserver reliability was assessed using interclass correlation coefficients (ICC). TT-PCL distances were also assessed to establish mean values in patellar instability patients. The ability of excessive TT-PCL and TT-TG distances to predict recurrent instability was assessed by comparing odds ratios, sensitivities, and specificities. RESULTS: Interobserver reliability was excellent for both TT-TG (ICC = 0.978) and TT-PCL (ICC = 0.932). The mean TT-PCL in these 59 knees was 21.7 mm (standard deviation 4.1 mm). Twelve (20 %) of 59 knees had a single dislocation, and 47 (80 %) exhibited 2 or more dislocations. The odds ratios, sensitivities, and specificities of a TT-TG distance ≥20 mm for identifying patients with recurrent dislocation were 5.38, 0.213, and 1.0, respectively, while those of a TT-PCL distance ≥24 mm were 1.46, 0.298, and 0.583, respectively. Of the 10 knees with a TT-TG distance ≥20 mm, all 10 (100 %) had recurrent instability, while 14 (73.7 %) of the 19 knees with a TT-PCL ≥24 mm experienced multiple dislocations (n.s.). CONCLUSION: Both TT-PCL and TT-TG can be measured on MRI with excellent interobserver reliability. In this series, the mean TT-PCL value in patients with patellar instability was 21.8 mm, but the range was broad. A TT-PCL distance ≥24 mm was found to be less predictive of recurrent instability in this series. For patients experiencing multiple episodes of patellar instability in the setting of a normal TT-TG distance, obtaining the TT-PCL measurement may provide a more focused assessment of the tibial contribution to tubercle lateralization. LEVEL OF EVIDENCE: III.

Long-term rate of graft failure after ACL reconstruction: a geographic population cohort analysis.

PURPOSE: Graft failure following anterior cruciate ligament reconstruction (ACLR) is a devastating injury among patients returning to activity. The goals of this study were to define the long-term rate of graft failure after ACLR in the general population and evaluate factors associated with graft failure. METHODS: This long-term observational study included a population-based incidence cohort of patients who underwent primary ACLR after diagnosis with new-onset, isolated ACL tears between 1990 and 2010. For all patients, a chart review was performed to collect information related to the initial injury, treatment, and outcomes. Patients were retrospectively followed to determine the incidence of graft failure following ACLR. RESULTS: The study cohort consisted of 1355 patients with new-onset, isolated ACL tears treated with ACLR. At a mean follow-up of 10.0 years (±6.4 years) following ACLR, a total of 72 patients (5.3 %) sustained ipsilateral graft failure. The graft survival following ACLR was 99.7 % at 1 year, 96 % at 5 years, 94 % at 10 years, 93 % at 15 years, 92 % at 20 years and 91 % at 25 years. Among patients 22 years or younger (n = 571), the rate of graft failure was significantly higher compared to patients older than 22 years (6.3 vs. 4.6 %, p = 0.04). The rate of graft failure decreased significantly over the 21-year observation period of this study (p < 0.0001). CONCLUSIONS: Among all patients receiving primary ACLR, graft failure remains an uncommon but functionally devastating outcome with an estimated graft survival rate of 91 % at 25 years following surgery. Patients aged 22 or younger had a significantly higher rate of graft failure than older patients. The rate of graft failure decreased over the 21-year span of this study. LEVEL OF EVIDENCE: Retrospective case series, Level IV.