Prospective Multicenter Randomized Controlled Trial of Surgical Versus Nonsurgical Treatment for Acute Rockwood Type 3 Acromioclavicular Injury.

Background: Evidence for the superiority of surgical versus nonsurgical treatment of Rockwood type 3 acromioclavicular joint (ACJ) dislocation is still lacking. Hypothesis: It was hypothesized that surgical treatment will outperform nonsurgical treatment. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: A prospective randomized trial involving 4 study centers was performed from January 1, 2011, to March 31, 2016. A total of 85 patients with acute Rockwood type 3 ACJ dislocations were allocated randomly to receive either nonsurgical or surgical treatment. A total of 70 patients were treated as allocated, and 8 patients made an early crossover from nonsurgical to surgical treatment, leaving 47 patients treated surgically and 31 patients nonsurgically. All patients were followed up longitudinally, including clinical evaluation using the Constant score and standardized radiographic evaluation, with final follow-up after 2 years. Results: At no follow-up time point was there a significant difference in Constant score between the surgically and nonsurgically treated patients. Radiographic analysis showed not only an inferior coracoclavicular distance at all follow-up points for surgical treatment but also a higher incidence of posttraumatic osteoarthritis and heterotopic ossifications, without any negative clinical correlation. With regard to complications, 1 patient (3%) in the nonsurgical group underwent secondary surgical ACJ stabilization. The revision rate after surgical treatment was 17% (P < .001). Neither primary horizontal instability nor younger age were associated with inferior clinical outcomes after nonsurgical treatment. Conclusion: Surgical treatment of ACJ Rockwood type 3 injuries did not lead to superior functional outcomes. Neither younger age nor horizontal instability were associated with inferior outcomes after nonsurgical treatment. Surgical treatment led to a slower recovery and to higher complication and revision rates. Registration: ISRCTN registry (study ID: ISRCTN92265154).

Osteoarthritis Progression after ACL Reconstruction Was Significantly Higher Than That of the Healthy Contralateral Knees: Long-Term Follow Up Study of Mean 16.4 Years.

BACKGROUND: This study aimed to assess long-term progression of osteoarthritis (OA) after isolated anterior cruciate ligament (ACL) reconstruction in athletes compared to the healthy contralateral side. METHODS: The study included 15 patients and 30 knees with a mean age of 40 years (range, 35-46) years, none of whom had had revision surgery or an injury to the contralateral side. The mean follow-up period was 16.4 years (range, 13-22). Clinical and radiographic assessment included the Tegner activity scale (TAS), International Knee Documentation Committee (IKDC) score, Knee injury and Osteoarthritis Outcome Score (KOOS), and Kellgren and Lawrence (KL) grade. The long-term results of the injured knees were compared with the status of the healthy contralateral side and compared with previously published mid-term results of the same cohort of patients. RESULTS: Patients generally remained clinically asymptomatic or mildly symptomatic at final follow-up, which is reflected by a KOOS pain score of 33 points (maximum 36 points) and an IKDC total subjective score of 87% (maximum 100%). There was a significant difference between mid-term and final follow-up in terms of the function score of the IKDC subjective questionnaire (p = 0.031), compartment findings and donor site morbidity of the IKDC functional examination (both p = 0.034), and the total KOOS score (p = 0.047). The KL score indicated significant progression of OA from mid-term to final follow-up in the injured knees (p = 0.004) and healthy contralateral knees (p = 0.014). Mean OA grades of the injured knees were significantly higher compared with the healthy contralateral side (p = 0.006) at final follow-up, and two patients showed moderate to severe signs of OA in the injured knee. CONCLUSIONS: Although most patients remained clinically asymptomatic or mildly symptomatic, long-term progression of OA after isolated ACL reconstruction in athletes was significantly higher compared with the healthy contralateral knee.

Conservative treatment of acute traumatic posterior shoulder dislocations (Type A) is a viable option especially in patients with centred joint, low gamma angle, and middle or old age.

PURPOSE: Purpose of this study was to evaluate the mid- to long-term outcome after conservatively treated first-time posterior shoulder dislocations and to determine structural defects associated with failure. METHODS: In this multi-centric retrospective study, 29 shoulders in 28 patients with first-time acute posterior shoulder dislocation (Type A1 or A2 according to the ABC classification) and available cross-sectional imaging were included. Outcome scores as well as radiological and magnetic resonance imaging were obtained at a mean follow-up of 8.3 ± 2.7 years (minimum: 5 years). The association of structural defects with redislocation, need for secondary surgery, and inferior clinical outcomes were analysed. RESULTS: Redislocation occurred in six (21%) shoulders and nine shoulders (31%) underwent secondary surgery due to persistent symptoms. The posttraumatic posterior glenohumeral subluxation was higher in the redislocation group compared to the no redislocation group; however, statistical significance was not reached (61.9 ± 12.5% vs. 50.6 ± 6.4%). Furthermore, a higher adapted gamma angle was observed in the failed conservative treatment group versus the conservative treatment group, similarly without statistically significant difference (97.8° ± 7.2°, vs. 93.3° ± 9.7°). The adapted gamma angle was higher than 90° in all patients of failed conservative therapy and the redislocation group. An older age at the time of dislocation showed a significant correlation with better clinical outcomes (SSV: r = 0.543, p = 0.02; ROWE: r = 0.418, p = 0.035 and WOSI: r = 0.478, p = 0.045). Posterior glenohumeral subluxation after trauma correlated with a worse WOSI (r = - 0.59, p = 0.02) and follow-up posterior glenohumeral decentring (r = 0.68, p = 0.007). The gamma angle (r = 0.396, p = 0.039) and depth of the reverse Hill-Sachs lesion (r = 0.437, p = 0.023) correlated significantly with the grade of osteoarthritis at follow-up. CONCLUSION: Conservative treatment is a viable option in patients with an acute traumatic posterior shoulder dislocation with good outcome after mid- and long-term follow-up especially in patients with centred joint, low gamma angle, and middle or old age. LEVEL OF EVIDENCE: IV.

The "Trigonometric Technique" for simple measurement of volar angulation in boxers' fractures.

INTRODUCTION: Subcapital fractures of the 5th metacarpal bone (MCV) represent a common injury. Volar angulation measurement is essential for treatment decision-making and therefore needs a reliable and valid method. The purpose of the present study was to investigate a new technique for volar angulation measurement, called the "Trigonometric Technique" (TT), and to compare the TT with the reference standard based on computed tomography (CT). HYPOTHESIS: Quantifying volar angulation in MCV neck fractures with the TT shows no difference compared to the angle measured on CT scans. MATERIAL AND METHODS: Fifteen patients (14 men and 1 woman) with a mean age of 37±16years (range, from 16 to 72 years) who suffered MCV neck fracture and met the inclusion and exclusion criteria were selected for this prospective cohort study. Radiologic investigation included simple dorsopalmar (DP) radiographs and CT scans from the injured hand. Volar angulation measurements were performed by three observers at two time points comparing the TT to measurements obtained on CT scans. Intraclass correlation coefficients (ICC) were determined to assess inter- and intra-observer reliability. RESULTS: The TT showed a mean volar angulation of 39±5 degrees (range, from 26 to 46 degrees) compared to 41±7 degrees (range, from 28 to 54 degrees) on CT measurement, which revealed a significant correlation between the two measurement techniques (R=0.922, p<0.001). Overall, the inter-rater (R=0.977; 95% CI 0.945-0.992) as well as intra-rater (R=0.857; 95% CI 0.739-0.941) reliability for the volar angulation using the TT was excellent. CONCLUSION: The TT presented in this study uses plain radiography and trigonometric identities to precisely determine volar angulation in MCV neck fractures. The TT correlates excellently with the obtained volar angulation angles measured on CT scans. We recommend the TT for volar angulation measurement in boxer's fracture as a reliable alternative to the conventional techniques. However, rotational abnormalities may remain undetected and should therefore be ruled out during clinical examination. LEVEL OF EVIDENCE: II, study of diagnostic test.

Repair failure increases the risk of developing secondary glenohumeral osteoarthritis: A long-term follow-up after open repair of large subscapularis tendon tears.

BACKGROUND: The subscapularis musculotendinous unit provides a stabilizing effect on the glenohumeral joint and thus, enables normal active range of motion. As pathologies of the subscapularis tendon (SSC) are diagnosed with increased regularity, treatment strategies and their long-term consequences are of relevant interest. Therefore, the primary objective of this retrospective case series was to evaluate clinical and radiological long-term results after open repair of large SSC tears. HYPOTHESIS: Repair failure negatively influences clinical outcomes and the progression of secondary glenohumeral osteoarthritis (OA). METHODS: Between 1998 and 2007, 24 patients with traumatic large (Lafosse III and IV) SSC tears were treated with an open transosseous repair technique. Of those, 20 patients (83%) with a mean age of 55±8 years (range, from 31 to 68 years) at the time of surgery were subjected to a long-term follow-up after a mean of 14±3 years (range, from 10 to 18 years). The Subjective Shoulder Value (SSV), the Constant Score (CS), the University of California at Los Angeles (UCLA) Shoulder Score, and the American Society for Shoulder and Elbow Surgeons (ASES) Score were obtained. Magnetic resonance imaging (MRI) was performed to evaluate tendon integrity. The progression of secondary glenohumeral OA from pre- to postoperative was analyzed using the collective instability arthropathy (CIA) score. RESULTS: One patient (5%) had to undergo revision surgery due to a symptomatic re-tear of the SSC tendon. Besides that, the mean SSV of the affected shoulder was 83%±12, the CS 78±10, the UCLA 32±2, and the ASES 89±14 points, respectively. MRI revealed a re-tear of the SSC tendon in 4 patients (29%). On the affected shoulder, glenohumeral OA progressed significantly from pre- (CIA, 0.3±0.5) to postoperative (CIA, 1.7±0.9; p=0.003) and was significantly associated with repair failure (p=0.040). CONCLUSION: Open repair of large SSC tears yielded good clinical long-term results. Nevertheless, repair failure was common and, in the further course, negatively affected clinical outcomes and the progression of secondary glenohumeral OA. LEVEL OF EVIDENCE: IV; retrospective case series.

Glenoid morphology is associated with the development of instability arthropathy.

BACKGROUND: Instability arthropathy (IA) is a major long-term concern in patients with anterior shoulder instability. This study investigated the association of glenoid morphology with the development of IA. METHODS: The study included 118 patients with unilateral anterior shoulder instability and available bilateral computed tomography scans. Instability-specific information was obtained from all patients. The glenoid morphology of the affected shoulder was compared with the nonaffected contralateral side resembling the constitutional preinjury glenoid shape. Both shoulders were evaluated independently by 3 observers to assess the grade of IA according to a Comprehensive Arthropathy Rating (CAR) system. Associations between IA and the glenoid morphology parameters were investigated. RESULTS: The average glenoid retroversion (P < .001), glenoid depth (P < .001), glenoid diameter (P < .001), and the bony shoulder stability ratio (P < .001) of the affected shoulder were significantly reduced compared with the contralateral side due to bony defects in 79.6% of the patients. The CAR of the affected side was significantly higher (P < .001), with more osteophytes (P = .001) and more sclerosis and cysts (P < .001). Differences in CAR (Δ-CAR) correlated positively with the age at the time of the computed tomography scan (P < .001), age at the initial dislocation (P = .001), size of the glenoid defect (P = .005), and the contralateral glenoid depth (P = .011), glenoid diameter (P = .016), and bony shoulder stability (P = .029), and negatively with glenoid retroversion of the affected side (P = .027). CONCLUSION: Development of IA arthropathy is associated not only with the age of the patients but also with morphologic parameters of the glenoid, including glenoid defect size and the constitutional glenoid concavity shape.

Anterior shoulder dislocation and concomitant fracture of the greater tuberosity: Clinical and radiological results.

BACKGROUND: Recurrence rates after primary traumatic shoulder dislocation are distinctly high. We hypothesized that concomitant isolated fractures of the greater tuberosity are associated with low rates of persistent instability but decreased range of motion. METHODS: Between 2007 and 2013, 66 consecutive shoulders in 64 patients were treated for primary shoulder dislocation combined with an isolated fracture of the greater tuberosity with either a nonsurgical (48 shoulders, 72.7%) or surgical (18 shoulders, 27.3%) treatment approach. In all, 55 cases (83.3%) were available for clinical follow-up examination after an average of 59.0 ± 20.7 months (range: 25-96 months) and of these, 48 (72.7%) patients consented to radiological evaluation to determine healing and position of the greater tuberosity. RESULTS: The mean range of motion of the affected shoulder was significantly decreased by 9° of elevation (p = 0.016), 11° of abduction (p = 0.048), 9° of external rotation in 0° of abduction (p = 0.005), and 10° of external rotation in 90° of abduction (p = 0.001), compared with the unaffected shoulder. The mean WOSI score was 373 ± 486 points, the mean Constant and Murley score was 75.1 ± 19.4 points, and the mean Rowe score was 83 ± 20 points. Three cases (5.5%) of re-dislocation were reported among the cohort, all of them were due to a relevant trauma. Radiological evaluation revealed anatomically healed fragments in 31 shoulders (65%), dislocation of the fragment in ten shoulders (21%), impaction into the humeral head in four shoulders (8%), and absorption in three shoulders (6%). CONCLUSION: A concomitant isolated fracture of the greater tuberosity leads to low recurrence rates along with a significant decrease in range of motion after primary traumatic anterior shoulder dislocation.

A prospective injury surveillance study in canyoning.

INTRODUCTION: Little is known about injuries in canyoning. It was the purpose of this study to determine injury rates, patterns, causes and risk factors in canyoning; and to identify targets for future injury prevention strategies. METHODS: From May to October 2015, 109 participants from 17 different countries were prospectively followed via a monthly e-mail-based questionnaire. RESULTS: During 13,690 h of canyoning, 57 injury-events occurred. The overall injury-rate was 4.2 injuries/1000 h of canyoning. The hand (23%) and lower leg and foot (25%) were most frequently involved. Most of the injuries were mild (n = 27, 49%) and limited to the soft-tissue. There were seven severe injuries (12%) with two lateral malleolar fractures, both necessitating surgery. The majority of injuries were due to material failure (44%) and significantly more injury-events were reported when the tour included rappelling (p = 0.037). Canyoning guides suffered from significantly less injuries compared to beginners and advanced canyoneers (p < 0.001). CONCLUSIONS: The majority of canyoning injuries are mild. On the other side, roughly one-tenth suffered from severe injury. Canyoning guides are less prone to injury-events and beginners should consider performing tours with experienced guides. Notwithstanding, rappelling was the most common activity associated with an injury and the material used was deemed causative for an injury-event in almost half of all cases. Further improvement in canyoning equipment, frequent equipment service, and instructional courses to ensure adequate employment of equipment might minimize the risk of getting injured.

Femoral and tibial graft tunnel parameters after transtibial, anteromedial portal, and outside-in single-bundle anterior cruciate ligament reconstruction.

BACKGROUND: Anatomic graft tunnel placement is recommended in anterior cruciate ligament (ACL) reconstruction to restore knee joint stability and function. Transtibial (TT), anteromedial portal (AMP), and outside-in (OI) retrograde drilling surgical techniques have been described for tibial and femoral bone tunnel preparation. PURPOSE/HYPOTHESIS: The purpose of this study was to evaluate the bone tunnel parameters and compare the ability of 3 different surgical techniques to achieve placement of the ACL femoral and tibial bone tunnels at the center of the native ACL femoral and tibial attachment sites. The hypothesis was that tunnel placement using an AMP or OI technique would result in optimized tunnel parameters and more closely reconstruct the center of the native ACL femoral attachment site. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: The study population consisted of 100 patients undergoing anatomic single-bundle ACL reconstruction using multiple-stranded hamstring tendon grafts. In group 1 (n = 36), the femoral tunnel was drilled using a TT surgical technique; in group 2 (n = 32), the femoral tunnel was drilled through an AMP; and in group 3 (n = 32), the femoral tunnel was created by use of an OI technique with retrograde drilling. Computed tomography (CT) scans were obtained postoperatively, and characteristics of femoral and tibial tunnel apertures were correlated to femoral and tibial measurement grid systems. The position of the resulting tibial and femoral bone tunnels for each group was compared with the center of the native ACL attachment sites. RESULTS: There were statistically significant differences (P < .05) for the ACL femoral tunnel between the 3 groups with respect to intercondylar height, total tunnel length, graft fixation length, tunnel axis, and tunnel entry angle. Statistically significant differences (P < .05) were found for the ACL tibial tunnel with respect to anteroposterior tunnel position and sagittal tunnel axis between the TT and both the OI and AMP techniques. The OI surgical technique produced more oblique and anatomically correct femoral tunnel apertures and longer femoral tunnel lengths compared with the AMP technique. Both AMP and OI techniques resulted in a more precise replication of intercondylar tunnel depth and height. There was no statistically significant difference for graft fixation length between the AMP and OI techniques. CONCLUSION: The AMP and OI surgical techniques were superior in positioning the ACL femoral tunnel at the center of the native ACL attachment site compared with the TT technique. An acceptable graft fixation length was obtained for all 3 surgical techniques.

Quantification of tibial bone loss in antegrade versus retrograde tunnel placement for anterior cruciate ligament reconstruction.

PURPOSE: Tibial bone destruction during primary graft tunnel placement and tibial bone loss following tunnel enlargement represent major challenges in revision reconstruction of the anterior cruciate ligament (ACL). Initial all-inside ACL reconstruction facilitates the preparation of tibial bone sockets rather than full tunnels that potentially preserve tibial bone stock. The purpose of this study was to comparatively assess length, diameter and volume of tibial graft tunnels following all-inside and conventional ACL reconstruction. METHODS: Postoperative computed tomography (CT) scans of 59 patients were assessed following ACL reconstruction. In 35 patients we used conventional antegrade tibial tunnel drilling and in 24 all-inside retrograde tibial bone sockets. Imaging analysis included total, minimal and maximal tunnel length and tunnel diameter. Tunnel volumes were calculated corresponding to these parameters. RESULTS: Statistically significant group differences (p < 0.01) could be detected for tibial tunnel volume, length and diameter between conventional antegrade and all-inside retrograde tibial bone tunnels and sockets, respectively. CONCLUSIONS: Compared with conventional techniques, all-inside retrograde drilling of tibial bone sockets is effective in preserving significant bone stock, which might be beneficial for revision reconstruction in cases of eventual primary graft failure.

The predictive effect of anatomic femoral and tibial graft tunnel placement in posterior cruciate ligament reconstruction on functional and radiological outcome.

PURPOSE: Biomechanical reports have advocated anatomic graft tunnel placement for reconstruction of the posterior cruciate ligament (PCL) to restore knee joint stability and facilitate optimal functional outcome. However, in vivo investigations that correlate tunnel position to functional results are lacking so far. This study evaluates the anatomic accuracy of femoral and tibial tunnel apertures on postoperative computed tomography (CT) scans and compares these findings to subjective and objective clinical outcome parameters. METHODS: After single-bundle PCL reconstruction, 29 patients were stratified into several subgroups according to the anatomic accuracy of femoral and tibial tunnel apertures measured on postoperative CT scans. A threshold value for the centres of the tunnel apertures was determined using a measurement grid system as a radiographic reference. To evaluate the functional and radiological results, visual analogue scale, International Knee Documentation Committee (IKDC), Tegner, Lysholm, Knee Injury and Osteoarthritis Outcome Score and osteoarthritis scores were obtained. RESULTS: Comparison between functional outcome and tunnel position yielded a statistically significant difference for subjective IKDC score and angle segment α and for objective stability and tunnel position P3 but no statistically significant difference with respect to intercondylar depth, intercondylar height and tibial tunnel position P2. No correlation was found between anatomic tunnel position and present or progressive osteoarthritis on follow-up. Of the patients, 72 % classified their result as excellent and good and 90 % would repeat surgical treatment. CONCLUSIONS: Despite a small sample size and subject to the threshold values we used, our data indicate a potentially minor effect of anatomic tunnel placement on midterm functional outcome following PCL reconstruction.

The biomechanical characteristics of arthroscopic tibial inlay techniques for posterior cruciate ligament reconstruction: in vitro comparison of tibial graft tunnel placement.

PURPOSE: The hypothesis of the present study was that the biomechanical properties of arthroscopic tibial inlay procedures depend on tibial graft bone block position. METHODS: Five paired fresh-frozen human cadaveric knee specimens were randomized to a reconstruction with quadriceps tendon placing the replicated footprint either to the more proximal margin of the remnants of the anatomical PCL fibrous attachments (group A) or to the distal margin of the anatomical PCL fibrous attachments at the edge of the posterior tibial facet to the posterior tibial cortex in level with the previous physis line (group B). The relative graft-tibia motions, post cycling pull-out failure load and failure properties of the tibia-graft fixation were measured. Cyclic displacement at 5, 500 and 1,000 cycles, stiffness and yield strength were calculated. RESULTS: The cyclic displacement at 5, 500 and 1,000 cycles measured consistently more in group A without statistically significant difference (4.11 ± 1.37, 7.73 ± 2.73 and 8.18 ± 2.75 mm versus 2.81 ± 1.33, 6.01 ± 2.37 and 6.46 ± 2.37 mm). Mean ultimate load to failure (564.6 ± 212.3) and yield strength (500.2 ± 185.9 N) were significantly higher in group B (p < 0.05). CONCLUSION: Replicating the anatomical PCL footprint at the posterior edge of the posterior tibial facet yields higher pull-out strength and less cycling loading displacement compared to a tunnel position at the centre of the posterior tibial facet.

Outcomes after shoulder arthroplasty revision with glenoid reconstruction and bone grafting.

PURPOSE: Extensive glenoid bone loss after failed shoulder arthroplasty represents a challenge for revision arthroplasty. Treatment options vary widely and have been a source of controversy among experts. METHODS: Between 2004 and 2010, a total of 17 patients underwent glenoid reconstruction surgery using an autologous iliac crest bone graft and secondary revision arthroplasty due to extensive glenoid bone loss after failed previous total shoulder arthroplasty. The outcomes were assessed by means of clinical examination, Constant score, and bi-plane radiography as well as pre-, postoperative and follow-up CT. RESULTS: Before the revision surgery, the mean Constant score was 24 ± 17 and improved to 40 ± 13 after the glenoid rebuilding and revision arthroplasty. CT imaging revealed adequate glenoid bone stock restoration with no relevant graft resorption or loosening of the glenoid. The average postoperative antero-posterior diameter of the glenoid was 28 ± 3 mm which had decreased to 25 ± 3 mm at follow-up. The average postoperative version of the glenoid was 95.7° ± 6° and had decreased to 98.5° ± 4° at follow-up. Both the glenoid version and diameter had changed significantly (P < 0.001) comparing postoperative and follow-up CT-scans. CONCLUSION: Glenoid reconstruction surgery using an iliac crest bone-block autograft prior to revision arthroplasty represents a valuable salvage procedure in cases of extensive glenoid bone loss after primary shoulder arthroplasty. Sufficient glenoid bone stock restoration is indispensable for reliable fixation of glenoid components and in turn a satisfactory clinical outcome.

Clinical and computed tomography-radiologic outcome after bony glenoid augmentation in recurrent anterior shoulder instability without significant glenoid bone loss.

BACKGROUND: The presence of a significant bony defect in anterior shoulder instability cases warrants glenoid reconstruction surgery typically by means of an autograft. Some surgeons use the same graft techniques even in the absence of a significant bony defect, thus augmenting the glenoid surface. The goal of this study is to investigate the clinical and computed tomography-radiologic outcome after glenoid augmentation surgery. METHODS: Between 2006 and 2011, 11 patients with recurrent anterior shoulder instability and glenoid bone loss of 5% or less were treated with an iliac crest autograft. Of the patients, 9 were available for follow-up at a mean of 34.6 months (range, 12 to 80 months), including apprehension testing, Western Ontario Shoulder Instability Index, Rowe score, Simple Shoulder Value, and 3-dimensional computed tomography examination. RESULTS: The mean Rowe score achieved was 85.0 points (range, 51 to 100 points); Simple Shoulder Value, 80.5 points (range, 30 to 100 points); and Western Ontario Shoulder Instability Index, 373.5 points (range, 61 to 878 points). Two patients reported a recurrence of instability, and one featured a positive apprehension test. The mean glenoid surface area was 96.5% (95% confidence interval [CI], 95.5% to 97.4%) preoperatively, increased after graft implantation to 119.5% (95% CI, 105.6% to 133.3%), and decreased to 102.8% (95% CI, 98.6% to 107.1%) at follow-up, concordant to an intact glenoid surface area. From preoperatively to follow-up, the mean increase in glenoid surface area was 6.4% (95% CI, 2.1% to 10.6%; P = .008); in concavity diameter, 2.0 mm (95% CI, -0.9 to 4.9 mm; P = .168); in concavity depth, 0.9 mm (95% CI, 0.3 to 1.5 mm; P = .005); and in concavity retroversion, 2.4° (95% CI, -1.2° to 6.1°; P = .178). CONCLUSION: Because of anatomic bony remodeling processes, glenoid augmentation surgery seems to be subject to extensive graft osteolysis and, consequently, unsatisfactory clinical outcome in terms of stability in some cases.

The medial-ridge sign as an indicator of anterior glenoid bone loss.

BACKGROUND: The goal of this study was to investigate the incidence of a medial bony ridge at the scapular neck in patients with recurrent anterior shoulder instability and analyze its reliability in identifying anterior glenoid rim bone loss. METHODS: A total of 109 shoulders in 105 consecutive patients underwent primary surgical stabilization for recurrent anterior shoulder instability with preoperative 2-dimensional and 3-dimensional computed tomography (CT) evaluation. The CT images of each affected shoulder were analyzed for the extent of anterior glenoid bone loss and the presence of a "medial-ridge sign." The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the medial-ridge sign were calculated for different sizes of glenoid rim defects. RESULTS: A positive medial-ridge sign was detected in 77.1% of the shoulders. The sensitivity of the medial-ridge sign ranged from 81.6% (95% confidence interval [CI], 73.0%-87.9%) for defects greater than 0% to 100% (95% CI, 82.4%-100%) for defects ≥20%. The PPV of the medial-ridge sign decreased from 100% for defects >0% to 11.9% for defects ≥25%. The specificity of the medial-ridge sign decreased from 100% (95% CI, 61.0-100%) for defects >0%, to 25.3% (95% CI, 17.7%-34.6%) for defects ≥25%. The NPV of the medial-ridge sign increased from 24.0% for defects >0% to 100% for defects >20%. CONCLUSION: The medial-ridge sign represents a CT-based radiologic sign with high sensitivity and NPV for identification of significant anterior glenoid rim defects in case of recurrent anterior shoulder instability.

Effect of anatomic bone grafting in post-traumatic recurrent anterior shoulder instability on glenoid morphology.

BACKGROUND: Shoulder stability primarily depends on concavity compression, which relies on the concave shape of the glenoid not mere glenoid width. This study analyzed the effect of anatomic glenoid reconstruction surgery on concavity morphology. METHODS: Thirty-one consecutive patients with recurrent anterior shoulder instability and glenoid bone loss underwent surgical stabilization using the J-bone graft. Twenty patients were available for preoperative, postoperative, and 1-year follow-up computed tomography scans. On standardized axial images, the change over time of the glenoid concavity extent, depth, version, and step-formation was measured and compared with the unaffected side. RESULTS: The mean preoperative concavity extent was 82.3% and increased (P < .001) after surgery to 113.1% before decreasing (P < .001) to 99.2% at follow-up concordant to the contralateral side (P = .75). The mean concavity depth was 56.6% preoperatively, increased to 226.4% postoperatively (P < .001), and diminished to 149.2% at follow-up (P < .001). Affected glenoids showed an average loss of -6.0° of retroversion preoperatively, with an increase to +5.6° postoperatively (P < .001) and a decrease to +0.2° at follow-up (P < .001). The average step-formation on the articular surface after graft insertion diminished significantly, from 2.3 mm postoperatively to 0.3 mm at follow-up (P < .001). CONCLUSION: Anatomic glenoid reconstruction surgery using the J-bone graft provides temporary overcorrection of the glenoid concavity extent, depth, and version, with subsequent normalization due to physiologic remodeling processes.

Reliability of a new standardized measurement technique for reverse Hill-Sachs lesions in posterior shoulder dislocations.

PURPOSE: The purpose of this study was to determine whether standardized measurements are more reliable than mere estimation in determining the extent of the defect in reverse Hill-Sachs lesions. METHODS: Twelve patients with 13 reverse Hill-Sachs lesions and available computed tomographic scans were included in this study. Based on the computed tomographic scans, estimation and measurement of the defect size in reverse Hill-Sachs lesions using a novel standardized method were carried out twice by 6 observers (3 experts and 3 residents), with an interval of 3 months between observations. To assess and compare the reliability of the estimation of the defect size and the measurement of the defect size, intraclass correlation coefficients were computed. RESULTS: Estimation of the defect size showed a low interobserver reliability of 0.61 (95% confidence interval [CI], 0.38 to 0.83) and 0.47 (95% CI, 0.24 to 0.74) and a moderate intraobserver reliability of 0.71 (95% CI, 0.51 to 0.89). The estimations of the different observers showed statistically significant differences (P < .001). The standardized measurements reached high interobserver reliability (at least ≥0.81) and excellent intraobserver reliability (at least ≥0.88). Residents provided less reliable estimations compared with experts; however, they obtained similarly high reliability when applying the standardized measurements. CONCLUSIONS: The mere estimation of the size of reverse Hill-Sachs lesions showed poor reliability, raising the concern for potential overestimation or underestimation in clinical practice. Standardized measurements, which showed good reliability, should be used whenever analyzing the size of a reverse Hill-Sachs defect. LEVEL OF EVIDENCE: Level IV, diagnostic case series.

The importance of CT for the pre-operative surgical planning in recurrent anterior shoulder instability.

BACKGROUND: MRI is the current pre-operative imaging standard in recurrent anterior shoulder instability; however, CT has increasingly gained interest due to its advantages in the detection of bony glenoid defects. This study compares the value of CT imaging and MRI for pre-operative surgical planning in recurrent anterior shoulder instability. METHODS: Between 2006 and 2009, 83 patients presented to the author's department with recurrent anterior shoulder instability. For 48 patients, both, pre-operative MRI and CT images were available. The respective patho-morphological descriptions were retrospectively compared with the intra-operative findings. The effect of each imaging technique on the pre-operative surgical planning was analyzed and the accuracy in predicting the necessity of open versus arthroscopic surgery was compared. RESULTS: In determining the necessity of open versus arthroscopic surgery CT imaging rendered an inaccurate prediction in 4.8 % of the cases which is less than the 25.0 % calculated for MRI. (p = 0.019). MRI showed a low sensitivity (35.3 %) in the detection of significant glenoid bone defects (≥20 % of the glenoid width measured on en-face views using a best-fit circle technique) while CT imaging provided an accurate prediction of the intra-operative finding in all cases. CONCLUSION: Despite the advantages of MRI in the detection of soft tissue damages in recurrent anterior shoulder instability CT imaging proved to be more important for pre-operative planning by prevailing in the detection of glenoid defects. Therefore, the replacement of MRI as preoperative imaging standard with CT imaging is recommended.

No increased occurrence of osteoarthritis after anterior cruciate ligament reconstruction after isolated anterior cruciate ligament injury in athletes.

PURPOSE: To evaluate the long-term radiographic and clinical results of anterior cruciate ligament (ACL) reconstruction by comparing the injured knee with the contralateral knee in athletes with isolated ACL tear returning to preinjury sports. METHODS: Twenty-eight patients with isolated ACL tears without concomitant injuries at baseline returning to previous sports were selected. ACL reconstruction was performed with patella or hamstring tendon graft. Conventional radiographs and a 3-T magnetic resonance imaging study of both knees were obtained at a mean follow-up of 10 years after ACL reconstruction and were compared with each other. The International Knee Documentation Committee score and Tegner activity index were used for clinical evaluation and the Knee Injury and Osteoarthritis Outcome Score for evaluating self-reported knee function. RESULTS: The 3-T magnetic resonance imaging study showed positive signs of osteoarthritis in 33% of operated knees and 39% of nonoperated knees (P = .64). Conventional radiographs showed ongoing signs of radiographic osteoarthritis in 14% of uninjured knees according to Kellgren and Lawrence, in comparison with 21% of injured knees (P = .73). The functional outcomes between the injured knee and uninjured knee did not show any statistical differences. The mean postoperative International Knee Documentation Committee score was 89.2 ± 9.3 points, and the total Knee Injury and Osteoarthritis Outcome Score was 92.7 ± 7.8. The median preinjury Tegner score was 8 ± 2, corresponding to 7 ± 2 at follow-up. In 68% of patients, the Tegner score was unchanged from preinjury to follow-up. CONCLUSIONS: Athletes with an isolated ACL rupture showed no increased risk of the development of post-traumatic osteoarthritis in the long-term after ACL replacement when compared with the uninjured contralateral knee. Our findings support the evidence to perform ACL replacement in athletes. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Arthroscopic rotator cuff repair: a biomechanical comparison of the suture-bridge technique vs. a new transosseous technique using SutureButtons(®).

BACKGROUND: The suture-bridge technique using anchors as established transosseous-equivalent technique in arthroscopic rotator cuff repair was compared to a modified transosseous technique suitable for arthroscopic cuff repair. METHODS: In 10 fresh-frozen matched pairs of human cadaveric shoulders (mean age 67.1, SD 8.5 years), two different surgical techniques of cuff repair were tested: Group 1, using the suture-bridge technique with suture anchors, and Group 2, using two transosseous tunnels with SutureButtons(®). Lateral row fixation was performed in both groups using knotless implants. Cyclic displacement to gap formation of 2 and 5mm, linear stiffness, yield load, ultimate load, and mode of failure were recorded. FINDINGS: Gap formation at the tendon-to-bone interface of 2mm occurred after a mean of 219.5 (SD 590.7) cycles in Group 1 and after 750.0 (SD 1566.1) cycles in Group 2. Gap formation of 5mm occurred after 2331.6 (SD 2033.9) cycles (Group 1) and 2364.5 (SD 1994.2) cycles (Group 2), respectively. The yield and ultimate loads were 316.9 (SD 114.1)N and 375.9 (SD 131.2)N in Group 1, and 311.0 (SD 97.2)N and 363.8 (SD 107.6)N in Group 2, respectively. The linear stiffness was 40.3 (SD 10.4)N/mm in Group 1, and 41.6 (SD 13.2)N/mm in Group 2. There were no statistically significant intergroup differences. INTERPRETATION: The new transosseous technique using SutureButtons(®) achieves equivalent biomechanical properties to the established suture-bridge technique using anchors. A tendentially reduced primary gap formation may be of importance for repair healing during the early phase of rehabilitation.