Sex-Dependent Differences in Preoperative, Radiographic, and Intraoperative Characteristics of Patients Undergoing Hip Arthroscopy: Results From the Multicenter Arthroscopic Study of the Hip Group.

PURPOSE: To compare preoperative, radiographic, and intraoperative findings between male and female patients undergoing hip arthroscopy. METHODS: We performed a retrospective review of a multicenter registry of patients undergoing hip arthroscopy between January 2014 and January 2017. Perioperative data from patients who consented to undergo surgery and completed preoperative patient-reported outcome questionnaires were analyzed to determine the effect of sex on preoperative symptoms, patient-reported outcomes, radiographic measures, and surgical procedures. RESULTS: A total of 1,437 patients (902 female and 535 male patients) with a mean age of 34 years were enrolled in the study. Female patients reported greater pain preoperatively on a visual analog scale (55.42 vs 50.40, P = .001) and deficits in functional abilities as per the modified Harris Hip Score (53.40 vs 57.83, P < .001) and International Hip Outcome Tool 12 (31.21 vs 38.51, P = .001) than male patients. There was a significant difference in the alpha angle (67.6° in male patients vs 59.5° in female patients, P < .001) corresponding with a higher prevalence of cam deformity in male patients (94.6% vs 84.5%, P < .001). Male patients had less range of motion in flexion (-5.67°, P < .001), internal rotation (-8.23°, P < .001), and external rotation (-4.52°, P < .001) than female patients. Acetabular chondroplasty was performed in 58% of male patients versus 40.2% of female patients (P < .001). Acetabuloplasty was performed in 59.1% of male patients versus 43.9% of female patients (P < .001). CONCLUSIONS: Male and female patients undergoing hip arthroscopy differ statistically in terms of preoperative hip function, hip morphology, and self-reported functional deficits, as well as the prevalence of surgical procedures. However, they do not differ significantly in terms of symptom localization, duration, or onset. The observed differences in preoperative functional scores between sexes, although statistically significant, may not represent clinically meaningful differences. LEVEL OF EVIDENCE: Level III, retrospective cross-sectional study.

Effect of tibial tunnel diameter on femoral tunnel placement in transtibial single bundle ACL reconstruction.

PURPOSE: The purpose of this study was to identify the impact of tibial reamer size and placement on the position of femoral tunnel placement via a transtibial approach for anterior cruciate ligament (ACL) reconstruction. METHODS: Eight cadaveric knee specimens were fixed to a stationary table at 90° of flexion and neutral rotation. After removing the anterior capsule and patella, native joint anatomy was recorded with a digitizer (MicroScribe™; CNC Services, Amherst, VA) accurate to 0.05 mm. Tibial and femoral tunnels were drilled via a transtibial ACLR technique using the optimal tibial starting point described by Piasecki et al. On the tibial side, tunnels were drilled progressively with 6-, 7-, 8-, 9-, 10-, and 11-mm reamers. After each reaming, a beath pin was placed in the posterior aspect of the tibial tunnel, positioned relative to the native anatomic ACL femoral footprint, and digitized. Rhino software (McNeel, Seattle, WA) was used to geometrically determine the center of the native femoral footprint and measure in millimeters the relationship of this point with the femoral position achieved using a 7-mm offset femoral guide with each tibial tunnel size. The surface areas of each tibial and femoral insertion were measured using the insertional periphery data recorded with the digitizer. Statistical analysis of continuous variable data was performed with t tests; P values below 0.05 were deemed significant. RESULTS: The center of the femoral ACL footprint was reached with a 9-mm tibial tunnel in six knees, and with an 8-mm tunnel in two knees. A 6- or 7-mm tibial tunnel did not allow for anatomic positioning in any specimen, with femoral positioning significantly more superior than that achieved with a 9-, 10-, or 11-mm tibial tunnel (P < 0.01). The 6- and 7-mm tunnels produced errors of 4.6 ± 1.6 and 2.9 ± 0.5 mm, respectively. After use of the 11-mm tibial reamer, the average tibial tunnel length was 32.1 ± 2.6 mm. CONCLUSIONS: Limitations of a transtibial ACLR technique may result in non-anatomic femoral tunnel placement with tibial tunnel sizes smaller than 9 mm. However, tibial tunnels placed in the proximal entry position with at least a 9-mm tunnel size allowed anatomic femoral tunnel placement via a transtibial approach.

Assessment of glenoid chondral healing: comparison of microfracture to autologous matrix-induced chondrogenesis in a novel rabbit shoulder model.

BACKGROUND: Management of glenohumeral arthrosis in young patients is a considerable challenge, with a growing need for non-arthroplasty alternatives. The objectives of this study were to develop an animal model to study glenoid cartilage repair and to compare surgical repair strategies to promote glenoid chondral healing. METHODS: Forty-five rabbits underwent unilateral removal of the entire glenoid articular surface and were divided into 3 groups--untreated defect (UD), microfracture (MFx), and MFx plus type I/III collagen scaffold (autologous matrix-induced chondrogenesis [AMIC])--for the evaluation of healing at 8 weeks (12 rabbits) and 32 weeks (33 rabbits) after injury. Contralateral shoulders served as unoperated controls. Tissue assessments included 11.7-T magnetic resonance imaging (long-term healing group only), equilibrium partitioning of an ionic contrast agent via micro-computed tomography (EPIC-µCT), and histologic investigation (grades on International Cartilage Repair Society II scoring system). RESULTS: At 8 weeks, x-ray attenuation, thickness, and volume did not differ by treatment group. At 32 weeks, the T2 index (ratio of T2 values of healing to intact glenoids) was significantly lower for the MFx group relative to the AMIC group (P = .01) whereas the T1ρ index was significantly lower for AMIC relative to MFx (P = .01). The micro-computed tomography-derived repair tissue volume was significantly higher for MFx than for UD. Histologic investigation generally suggested inferior healing in the AMIC and UD groups relative to the MFx group, which exhibited improvements in both integration of repair tissue with subchondral bone and tidemark formation over time. DISCUSSION: Improvements conferred by AMIC were limited to magnetic resonance imaging outcomes, whereas MFx appeared to promote increased fibrous tissue deposition via micro-computed tomography and more hyaline-like repair histologically. The findings from this novel model suggest that MFx promotes biologic resurfacing of full-thickness glenoid articular injury.

Magnetic resonance imaging evaluation of normal glenoid length and width: an anatomic study.

PURPOSE: The purpose of this study was to evaluate the measured dimensions of the normal glenoid on sagittal magnetic resonance (MR) imaging to determine whether a fixed ratio of glenoid length and width can be determined. METHODS: MR images of 90 glenoids in 84 patients were analyzed. The mean age was 54.8 years, with 44 male and 40 female patients. Glenoid length and width at the widest dimension were measured and recorded by 3 independent examiners. The ratio of length to width and the ratio of the length of the superior pole at the widest point to the total length were calculated. Intraclass correlation coefficients, Spearman and Pearson correlations, regression analysis with cross validation, and coefficients of variation were calculated. RESULTS: The mean glenoid length was 37.5 ± 3.8 mm, whereas the mean width was 24.4 ± 2.9 mm. The mean ratio of length to width was 1.55 ± 0.1, whereas the mean ratio of the distance from the superior pole to the widest point to the total glenoid length was 0.64 ± 0.03. The calculated ratios were less variable than the absolute length and width. Cross validation of length for width showed a 95% prediction band width of 4.48 mm, with an average absolute error of prediction of 1.46 mm, and was equally specific when separated by gender. The width was equal to 0.65 times the length. CONCLUSIONS: Measurement of glenoid length and width using MR imaging results in a consistent ratio of length to width independent of patient age and gender, where the width was equal to 0.65 times the length at a point two-thirds along the inferosuperior axis. LEVEL OF EVIDENCE: Level IV, case series.

Clinical outcomes of reverse total shoulder arthroplasty in patients aged younger than 60 years.

BACKGROUND: Reverse total shoulder arthroplasty (RTSA) has been indicated primarily for patients aged older than 65 years with symptomatic rotator cuff deficiency, poor function, and pain. However, conditions that benefit from RTSA are not restricted to an elderly population. This study evaluates a consecutive series of RTSA patients aged younger than 60 years. METHODS: We evaluated 36 shoulders (mean age, 54 years) at a mean follow-up of 2.8 years (range, 24-48 months). Of these shoulders, 30 (83%) had previous surgery, averaging 2.5 procedures per patient. The preoperative conditions compelling RTSA were as follows: failed rotator cuff repair (12), fracture sequelae (11), failed arthroplasty (5), instability sequelae (4), cuff tear arthropathy (CTA) (4), and rheumatoid arthritis (2). Follow-up examinations included range-of-motion and strength testing, as well as Single Assessment Numeric Evaluation, visual analog scale, Simple Shoulder Test, American Shoulder and Elbow Surgeons (ASES), and Constant scores. Preoperative and postoperative radiographs were reviewed for component loosening and scapular notching. Failure criteria were defined as undergoing revision, having gross loosening, or having an ASES score below 50. RESULTS: The mean Single Assessment Numeric Evaluation score improved from 24.4 to 72.0; the visual analog scale pain score improved from 6 to 2.1. The Simple Shoulder Test score improved from 1.4 to 6.2, and the ASES score improved from 31.4 to 65.8. Active forward elevation improved from 56° to 121°. The normalized postoperative mean Constant score was 54.3. In 9 patients (25.0%), we recorded an ASES score below 50, and these cases were considered failures. CONCLUSION: RTSA can improve shoulder function in a younger, complex patient population with poor preoperative functional ability. This study's success rate was 75% at 2.8 years. This is a limited-goals procedure, and longer-term studies are required to determine whether similar results are maintained over time.

Medial unicompartmental knee arthroplasty in patients less than 55 years old: minimum of two years of follow-up.

Eighty-five fixed bearing medial unicompartmental arthroplasties were performed in 42 men and 33 women with a mean age of 49 years (range, thirty-three to fifty-five years old) at the time of surgery. At a mean of 4.0 years (range two to twelve years), the mean pre-operative Knee Society score improved from 49 to 95.1 points (P<0.0001) and the mean UCLA activity score was 7.5 (range 5 to 9). Three knees underwent revision to a total knee arthroplasty; two for arthritic progression in the lateral compartment and one for pain. At the time of final follow-up, two knees (2.4%) demonstrated progressive Grade 4 arthritis of the patellofemoral compartment but were asymptomatic. There was no radiographic evidence of loosening, osteolysis, or premature polyethylene wear. Estimated survivorship was 96.5% at 10 years. UKA offered excellent early outcomes in this cohort of younger, active patients.

Transosseous-equivalent rotator cuff repair: a systematic review on the biomechanical importance of tying the medial row.

PURPOSE: Double-row and transosseous-equivalent repair techniques have shown greater strength and improved healing than single-row techniques. The purpose of this study was to determine whether tying of the medial-row sutures provides added stability during biomechanical testing of a transosseous-equivalent rotator cuff repair. METHODS: We performed a systematic review of studies directly comparing biomechanical differences. RESULTS: Five studies met the inclusion and exclusion criteria. Of the 5 studies, 4 showed improved biomechanical properties with tying the medial-row anchors before bringing the sutures laterally to the lateral-row anchors, whereas the remaining study showed no difference in contact pressure, mean failure load, or gap formation with a standard suture bridge with knots tied at the medial row compared with knotless repairs. CONCLUSIONS: The results of this systematic review and quantitative synthesis indicate that the biomechanical factors ultimate load, stiffness, gap formation, and contact area are significantly improved when medial knots are tied as part of a transosseous-equivalent suture bridge construct compared with knotless constructs. Further studies comparing the clinical healing rates and functional outcomes between medial knotted and knotless repair techniques are needed. CLINICAL RELEVANCE: This review indicates that biomechanical factors are improved when the medial row of a transosseous-equivalent rotator cuff is tied compared with a knotless repair. However, this has not been definitively proven to translate to improved healing rates clinically.

Computed tomographic analysis of curved and straight guides for placement of suture anchors for acetabular labral refixation.

PURPOSE: The purpose of this study was to compare suture anchor placement in the acetabular rim between straight and curved drill guides regarding angle and distance of the suture anchor tip from the articular cartilage during labral refixation. METHODS: A total of 14 fresh-frozen cadaveric hips underwent arthroscopic labral incision from the 12 to 3 o'clock positions and subsequent repair with either a curved drill guide or a straight drill guide. These hips were then compared by computed tomographic imaging analysis by measuring the angle of suture anchor insertion and the distance of the tip of the suture anchor to the articular cartilage at the 1 o'clock, 2 o'clock, and 3 o'clock positions. RESULTS: The curved suture anchor (CSA) guide significantly increased the insertion angle (P = .009) and distance from the articular cartilage to anchor (P = .003) at the 1 o'clock position on the acetabulum. The angle of insertion at the 2 and 3 o'clock positions was greater for the CSA guide compared with the straight suture anchor (SSA) guide but did not reach statistical significance. CONCLUSIONS: A CSA guide was shown to be significantly more effective in increasing the angle of insertion of suture anchors and increased the distance of the suture anchor tip to the articular cartilage surface at the 1 o'clock position but not at the 2 or 3 o'clock position. CLINICAL RELEVANCE: The use of SSA guides can be difficult because of the osseous morphologic characteristics of the acetabular rim, leading to placement of the suture anchor away from the acetabular rim and therefore resulting in a nonanatomical refixation of the acetabular labrum. The use of a curved guide, flexible drill, and flexible suture anchor inserter may provide more precise placement of suture anchors in the acetabular rim.

Age-related differences in radiographic parameters for femoroacetabular impingement in hip arthroplasty patients.

PURPOSE: To compare the prevalence of femoroacetabular impingement (FAI) radiographic findings between patients aged younger than 50 years and those aged 50 years or older who underwent total hip arthroplasty. METHODS: Total hip arthroplasty patients aged younger than 50 years and those aged 50 years or older were identified retrospectively from a facility medical record database. Fifty patients from each group were randomly selected, and preoperative radiographs were collected. Dysplastic, inflammatory, post-traumatic, and osteonecrosis patients were excluded. Radiographs were evaluated for FAI-specific findings. Intraobserver and interobserver reliability was evaluated with κ statistics for categorical variables and intraclass correlation coefficients for continuous variables. An independent t test was used to compare continuous variables, χ(2) analysis was used for discrete variables, and a z ratio was used to analyze proportions. RESULTS: The mean age between the subgroups of patients aged younger than 50 years and those aged 50 years or older (43 years and 68 years, respectively) was significantly different (P < .05). Findings in the subgroup aged younger than 50 years included significantly more men (P < .001), decreased lateral joint space with maintained medial joint space (P < .05), significantly greater alpha angle on both the anteroposterior view and the frog-leg lateral view (P < .05), significantly higher Tönnis and Sharp angles (P < .01), and significantly lower center-edge angle (P < .001). CONCLUSIONS: This retrospective case series shows an increased prevalence of FAI findings (specifically cam pathology) in a patient population aged younger than 50 years undergoing total hip arthroplasty when compared with a cohort aged 50 years or older. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Screw fixation of an OCD loose body: 21-year results.

Osteochondritis dissecans (OCD) lesions can progress to loose body formation for which treatment is controversial and may involve excision or fixation. There is a paucity of published data regarding long-term outcomes following OCD loose body fixation. This case report presents an interval follow-up of a patient from a previous small case series of individuals who underwent open reduction internal fixation of large, lateral OCD loose bodies. At 21-year follow-up the patient has full, pain-free range of motion, and has not required subsequent surgery. This case, to our knowledge, is the first to report over 20-year follow-up from fixation of an OCD loose body and demonstrates a good long-term outcome. Clinicians should consider replacement and fixation of an OCD loose body when possible, as this may provide the best chance of long-term function.

The role of platelet-rich plasma in arthroscopic rotator cuff repair: a systematic review with quantitative synthesis.

PURPOSE: Despite the theoretic basis and interest in using platelet-rich plasma (PRP) to improve the potential for rotator cuff healing, there remains ongoing controversy regarding its clinical efficacy. The objective of this systematic review was to identify and summarize the available evidence to compare the efficacy of arthroscopic rotator cuff repair in patients with full-thickness rotator cuff tears who were concomitantly treated with PRP. METHODS: We searched the Cochrane Central Register of Controlled Trials, Medline, Embase, and PubMed for eligible studies. Two reviewers selected studies for inclusion, assessed methodologic quality, and extracted data. Pooled analyses were performed using a random effects model to arrive at summary estimates of treatment effect with associated 95% confidence intervals. RESULTS: Five studies (2 randomized and 3 nonrandomized with comparative control groups) met the inclusion criteria, with a total of 261 patients. Methodologic quality was uniformly sound as assessed by the Detsky scale and Newcastle-Ottawa Scale. Quantitative synthesis of all 5 studies showed that there was no statistically significant difference in the overall rate of rotator cuff retear between patients treated with PRP and those treated without PRP (risk ratio, 0.77; 95% confidence interval, 0.48 to 1.23). There were also no differences in the pooled Constant score; Simple Shoulder Test score; American Shoulder and Elbow Surgeons score; University of California, Los Angeles shoulder score; or Single Assessment Numeric Evaluation score. CONCLUSIONS: PRP does not have an effect on overall retear rates or shoulder-specific outcomes after arthroscopic rotator cuff repair. Additional well-designed randomized trials are needed to corroborate these findings. LEVEL OF EVIDENCE: Level III, systematic review of Level I, II, and III studies.

Relationship of Average Outcomes Scores and Change in Status Requires Further Interpretation Between 1 and 2 Years Following Hip Arthroscopy.

BACKGROUND: Previous studies have demonstrated a clinically impactful change in patients between 1 and 2 years after hip arthroscopy. Assessment of differences in patient-specific factors between patients who remain the same and those who change (ie, either improve or decline) could provide valuable outcome information for orthopaedic surgeons treating those patients. PURPOSE: To identify patients who experienced change in functional status between 1 and 2 years after hip arthroscopy for femoroacetabular impingement syndrome and assess differences in patient-specific factors between those who improved, remained the same, or declined in functional status. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Prospectively collected data for patients who underwent hip arthroscopy at 1 of 7 centers were analyzed retrospectively at 1 year and 2 years postoperatively. Patients were categorized as "improved,""remained the same," or "declined" between 1- and 2-year follow-up based on the 12-item International Hip Outcome Tool (iHOT-12) minimal clinically important difference (MCID) value. A 1-way analysis of variance was used to assess differences in iHOT-12 scores, age, body mass index (BMI), alpha angle, and center-edge angle (CEA) between groups. Chi-square analyses were used to assess differences in the proportions of male and female patients in the outcome groups. RESULTS: The study included 753 patients (515 women and 238 men), whose mean ± SD age was 34.7 ± 12 years. Average 1-year (±1 month) and 2-year (±2 months) iHOT-12 scores for all patients were 73.7 and 74.9, respectively. Based on the calculated MCID of ±11.5 points, 162 (21.5%) patients improved, 451 (59.9%) remained the same, and 140 (18.6%) declined in status between 1- and 2-year follow-up. Those who improved between 1 and 2 years had lower 1-year iHOT-12 scores (P < .0005). We found no difference in age, BMI, alpha angle, CEA, or sex between groups (P > .05). CONCLUSION: Between 1- and 2-year follow-up assessments, 21.5% of patients improved and 18.6% declined in self-reported functional status. Those with iHOT-12 scores indicating abnormal function at 1 year improved beyond the MCID at 2 years follow-up. Thus, any decisions about the failure or success of arthroscopic hip procedures should not be made until at least the 2-year follow-up. Failing to thrive at 1-year follow-up may not accurately predict outcomes at year 2 or beyond. This could potentially decrease the perceived need for revision surgery in patients who do not thrive before 2-year follow-up.

Intraoperative molds to create an articulating spacer for the infected knee arthroplasty.

BACKGROUND: Chronic infections in TKA have been traditionally treated with a two-stage protocol incorporating a temporary antibiotic-loaded cement spacer. The use of a static as opposed to an articulating spacer is controversial. Some surgeons believe a static spacer results in a higher rate of infection eradication, whereas others believe an articulating spacer provides equivalent rates of infection control with improved function between stages and the potential for better eventual range of motion. QUESTIONS/PURPOSES: We determined the rates of infection control and postoperative function for an articulating all-cement antibiotic spacer fashioned intraoperatively from prefabricated silicone molds. METHODS: We retrospectively reviewed 60 patients with an infected TKA using the same cement-on-cement articulating spacer. A minimum of 4 g antibiotic per package of cement was used when making the spacer. Complications and pre- and postoperative knee flexion, extension, and Knee Society scores were recorded. Bone loss associated with the spacer was determined radiographically and by intraoperative inspection of the bony surfaces at the second stage. Minimum followup was 24 months (mean, 35 months; range, 24-51 months). RESULTS: Seven patients (12%) became reinfected, four with an organism different from that identified at the index resection arthroplasty. One spacer femoral component broke between stages but did not require any specific treatment. We identified no bone loss between stages and no complications related to the cement-on-cement articulation. The mean pretreatment Knee Society scores of 53 improved to 79. The mean preoperative flexion of 90.6º improved to 101.3º at final followup. CONCLUSIONS: An articulating antibiotic spacer was associated with control of a deep periprosthetic infection in 88% of patients while allowing range of motion between stages. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Biceps tenodesis with interference screw fixation: a biomechanical comparison of screw length and diameter.

PURPOSE: To evaluate the effect of screw length and diameter on the mechanical properties of biceps tenodesis (BT) with an interference screw in 2 different locations (proximal and distal). METHODS: We randomized 42 fresh-frozen human cadaveric shoulders (mean age, 65 ± 8 years) into 6 groups (n = 7): arthroscopic proximal BT using 7 × 15-, 7 × 25-, 8 × 15-, or 8 × 25-mm interference screws or distal subpectoral BT with 7 × 15- or 8 × 15-mm interference screws. Each repaired specimen was mounted onto a materials testing machine, preloaded to 5 N for 2 minutes, cycled from 5 to 70 N for 500 cycles (1 Hz), and loaded to failure (1 mm/s). Displacement during cyclical loading, pullout stiffness, and ultimate load to failure were computed, and the mechanism of failure was noted. RESULTS: All failures occurred at the tendon-screw interface. There was no statistically significant difference in ultimate displacement among all groups in the ultimate load to failure, displacement at peak load, and stiffness. CONCLUSIONS: There is no difference in ultimate load to failure, displacement at peak load, and stiffness of BT with regard to screw length or diameter at both proximal and distal tenodesis locations. These data would support use of a smaller-diameter and shorter implant for BT both proximally and distally. CLINICAL RELEVANCE: The results may serve as a guide to the orthopaedic surgeon performing proximal BT in selecting the appropriate interference screw. When possible, we recommend using the smallest screw size available to minimize risk of stress fracture at the tenodesis site.

The vertical humeral osteotomy for stem removal in revision shoulder arthroplasty: results and technique.

HYPOTHESIS: Revision shoulder arthroplasty represents a complex and difficult problem for the treating surgeon, with multiple potential complications. In the setting of a well-fixed humeral component, removal can lead to fractures and compromise the outcome of the revision. The current study describes and evaluates the results of a novel vertical humeral osteotomy (VHO) for stem extraction. We hypothesized that the VHO will enable successful stem extraction without perioperative or postoperative fractures. MATERIALS AND METHODS: Twenty-seven patients were retrospectively identified who had a VHO for revision shoulder arthroplasty, with 23 patients available for final follow-up. Records and radiographs were reviewed for postoperative complications. Final follow-up was completed with the inclusion of shoulder scores. RESULTS: There were no perioperative or postoperative fractures on clinical examination and radiographic review at an average follow-up of 41 months. Average American Shoulder and Elbow Surgeons (ASES) score was 64.7 (contralateral ASES, 76.9), average Simple Shoulder Test was 6.3, and the visual analog score pain average was 1.3. There were no instability events. DISCUSSION: The glenoid is the more common site for failure in both hemiarthroplasty and total shoulder arthroplasty. This can lead to a difficult revision procedure if the ingrown or cemented humeral stem requires removal. CONCLUSION: In the current study, we found the VHO was an effective tool for the removal of the humeral prosthesis with no perioperative or postoperative fractures.

Biomechanical evaluation of a high tibial osteotomy with a meniscal transplant.

This study determines the biomechanical advantage and the optimal configuration of a high tibial osteotomy (HTO) and meniscus transplantation performed concurrently. Six cadaver knees were placed in a spatial frame, and an HTO was completed. Loading points between a mechanical 6 degrees of varus and 8 degrees ofvalgus were loaded to 800 N for medial meniscal intact, meniscectomized, and transplanted states. Posterior slope was also increased by 3 degrees in these specimens. Contact data was recorded. Peak pressures significantly increased in the meniscectomized state in every degree of varus/valgus (p < 0.05). For both peak and total medial compartment pressures, there was a significant drop (p < 0.001) between neutral and 3 degrees of valgus. Lateral compartment pressures linearly increased from varus to valgus orientation. There was no significant change in the pressure profile of the knee with a 3-degree increase in posterior slope. This biomechanical study confirms the hypothesis that an HTO improves the peak pressures in the medial compartment at all degrees of varus/valgus alignment in the setting of meniscal transplantation. Furthermore, the largest decrease in medial pressures was between neutral and 3 degrees of valgus, suggesting that perhaps neutral aligned knees could benefit from an HTO.

Retrospective analysis of arthroscopic management of glenohumeral degenerative disease.

PURPOSE: The purpose of this study was to examine the results of arthroscopic debridement for isolated degenerative joint disease of the shoulder. METHODS: We retrospectively identified 81 patients who had arthroscopic debridement to treat glenohumeral arthritis. Of these patients, 71 (88%) were available for follow-up. The preoperative Simple Shoulder Test score, American Shoulder and Elbow Surgeons score, Short Form 12 score, visual analog scale score for pain, and range of motion were recorded. These were compared against postoperative scores by use of the statistical paired t test. In addition, patients completed postoperative University of California, Los Angeles; Constant; and Single Assessment Numeric Evaluation scores. Forty-six preoperative radiographs were blindly evaluated and classified. Finally, the need for subsequent shoulder arthroplasty was recorded. RESULTS: The mean follow-up for the 55 patients who did not progress to arthroplasty was 27 months. The mean preoperative and postoperative American Shoulder and Elbow Surgeons, Simple Shoulder Test, and pain visual analog scale scores all significantly improved (P < .05). Furthermore, range of motion significantly improved (P < .05) in flexion, abduction, and external rotation. Additional postoperative scores were as follows: University of California, Los Angeles, 28.3; Single Assessment Numeric Evaluation, 71.1; Constant score for affected shoulder, 72.0; and Constant score for unaffected shoulder, 78.5. Of the patients, 16 (22%) underwent arthroplasty at a mean of 10.1 months after debridement. Radiographic review showed that 13 shoulders with a mean joint space of 1.5 mm and grade 2.4 arthrosis went on to have shoulder arthroplasty. In contrast, 33 shoulders with a mean joint space of 2.6 mm and grade 1.9 arthrosis did not go on to have shoulder arthroplasty. CONCLUSIONS: Patients with residual joint space and an absence of large osteophytes can avoid arthroplasty and have increased function with decreased pain after arthroscopic debridement for degenerative joint disease. Significant risk factors for failure include the presence of grade 4 bipolar disease, joint space of less than 2 mm, and large osteophytes. LEVEL OF EVIDENCE: Level IV, case series.

Biomechanical similarities among subscapularis repairs after shoulder arthroplasty.

HYPOTHESIS: Many authors suggest that subscapularis deficiency after shoulder arthroplasty has a negative effect on long-term outcomes. Thus, increasing emphasis has been placed on the technique for repair of the tendon. This study evaluated the biomechanical strength of 3 different repairs: osteotomy, tendon to bone, and a combined method. MATERIALS AND METHODS: Twenty-four paired shoulders from deceased donors were prepared for shoulder arthroplasty. The subscapularis tendon was removed/repaired with the lesser tuberosity in the osteotomy group, was removed periosteally in the bone-to-tendon group, and was tenotomized in the combined group. The tendon-to-bone repair used bone tunnels, and the combined construct added tendon-to-tendon fixation. A materials testing system machine was used for cycling. A digital motion analysis system with spatial markers was used for analysis. RESULTS: There were no significant differences (P > .05) in age, bone mineral density, or construct thickness. No statistically significant differences (P > .05) in elongation amplitude (P = .67) or cyclic elongation (P = .58) were detected within the constructs or between repair techniques. Failure testing revealed no differences in maximum load, stiffness, or mode of failure. DISCUSSION: There remains no consensus about the optimal method of repairing the subscapularis tendon during shoulder arthroplasty. Furthermore, the results of the current study do not support one technique over another with regard to initial fixation properties. All constructs investigated exhibited comparably robust biomechanical performance. Durability may, therefore, be more a result of healing potential than the specific construct chosen.

Reliability of hip range of motion measurement among experienced arthroscopic hip preservation surgeons.

The aim of this study was to determine (i) the reliability of hip range of motion measurement among experienced arthroscopic hip preservation surgeons and (ii) the magnitude of hip flexion change with posterior pelvic tilt. Five experienced arthroscopic hip preservation surgeons (5-18 years of hip surgery experience) performed passive hip range of motion (internal and external rotation), flexion (contralateral hip extended) and flexion with posterior pelvic tilt (contralateral hip maximally flexed) on five young healthy asymptomatic volunteers (three males, two females; 34.4 ± 10.7 years of age). Motion was measured via digital photography and goniometry. Inter-observer reliability was calculated via two-way mixed, single measures, intra-class correlation coefficient. Paired t-test was utilized to compare hip flexion (with contralateral hip extended) to hip flexion with posterior pelvic tilt (with contralateral hip in forced flexion). The reliabilities of measurements of hip flexion with posterior pelvic tilt and external rotation were excellent, that of hip flexion was fair, and that of hip internal rotation was poor. The magnitude of hip flexion increase with posterior pelvic tilt was 17.0° ± 3.0° (P < 0.001). The reliability of hip range of motion measurement by five experienced arthroscopic hip preservation surgeons was excellent for measures of hip flexion with posterior pelvic tilt and external rotation. Contralateral maximal hip flexion significantly increased ipsilateral hip flexion (approximately 17°). Level of Evidence: Diagnostic, level III (without consistently applied reference standard).

Meniscal allograft size can be predicted by height, weight, and gender.

PURPOSE: Our purpose was to determine if height, weight, and gender can be used to accurately predict proper meniscal allograft dimensions. METHODS: Data were obtained from the Joint Restoration Foundation (AlloSource, Centennial, CO) regarding meniscal size and patient characteristics from meniscal donors. Donor height, weight, sex, age, and anatomic meniscal dimensions were recorded for 930 donor menisci in 664 patients. Multivariate regressions were completed using gender, height, and weight as independent variables and lateral meniscus length, lateral meniscus width, medial meniscus length, and medial meniscus width as dependent variables. The regression formulas were then reapplied to the data in order to produce estimated meniscus dimensions based on donor height, weight, and gender. A 90:10 split of the data was used to validate the regression models. Predicted meniscal size was then compared to actual meniscal size and the results compared to current measurement techniques. RESULTS: Regression formulas showed the ability to predict meniscal size based on gender, height, and weight with standard deviations (SDs) equal to or less than current radiographic techniques (SD, 6.4% to 8.2%). Average differences between predicted size and actual size ranged from 5.2% to 6.5% for length and 5.2% to 6.0% for width. Patient height was found to be a much more powerful predictor of meniscal size than patient weight. Data from the 90:10 split of data validated the model on an independent sample. These validated outputs were then compared to contemporary techniques and found to have lower SDs and average error rates in the majority of cases. CONCLUSIONS: We have proposed a validated regression model that uses height, weight, and gender variables to accurately predict required allograft meniscal size. We compared it against previously published data for radiographic and magnetic resonance imaging sizing techniques and found it to produce results that were, overall, slightly more accurate. CLINICAL RELEVANCE: This model provides a novel method for sizing meniscal allografts.