Christopher R. Adams

Use of Preoperative Three-Dimensional Computed Tomography to Quantify Glenoid Bone Loss in Shoulder Instability

PURPOSE The purpose of this study was to determine if three-dimensional computed tomography (3-D CT) scans of the glenoid can be used to accurately quantify, by means of a glenoid index, bone loss in patients with anterior glenohumeral instability, and to compare the results with arthroscopic measurements to determine if the 3-D CT scan can preoperatively predict which patients with anterior glenohumeral instability will benefit from a bone grafting procedure. METHODS From 2003 to 2006, 188 patients with anterior glenohumeral instability underwent arthroscopic evaluation and treatment by the senior author (S.S.B.). Of 188 total patients, there were 25 patients ranging in age from 15 to 43 years (median, 19 years) who underwent 3-D CT evaluations of both shoulders followed by arthroscopy of the unstable shoulder. For an arthroscopically measured bone loss of less than 25% of the inferior glenoid diameter, an arthroscopic Bankart repair was performed; for a glenoid bone loss of greater than or equal to 25%, an open Latarjet reconstruction was performed. We defined the glenoid index as the ratio of the maximum inferior diameter of the injured glenoid compared to the maximum inferior diameter of the uninjured contralateral glenoid as calculated from the 3-D CT scans. If the glenoid index was greater than 0.75, the patient was predicted to benefit from an arthroscopic Bankart repair (the need for surgery and the type of surgery having been determined on the basis of arthroscopic measurements). However, if the glenoid index was less than or equal to 0.75, the patient was predicted to benefit from an open Latarjet procedure. The results of each patients glenoid index were compared with the arthroscopic decision to perform either an arthroscopic Bankart repair or an open Latarjet procedure. RESULTS Of the 25 patients included in this study, 13 patients underwent an open Latarjet procedure and 12 patients underwent an arthroscopic Bankart repair. The 3-D CT scans accurately predicted the arthroscopic decisions to perform an arthroscopic Bankart repair or open Latarjet in 24 (96%) of 25 cases (Fisher exact test; P < .001). CONCLUSIONS The glenoid index as calculated from the 3-D CT scan accurately predicted the requirement of a bone grafting procedure for 24 (96%) of 25 patients when the benchmark value of 0.75 was used. The 3-D CT scan can therefore be used by surgeons as an additional diagnostic tool for preoperative planning and patient counseling. LEVEL OF EVIDENCE Level III, development of diagnostic criteria with universally applied reference (nonconsecutive patients).

The Results of Arthroscopic Subscapularis Tendon Repairs

PURPOSE The purpose of this study was to evaluate patients after an arthroscopic subscapularis tendon repair to determine their intermediate-term results. METHODS The records of all patients who underwent an arthroscopic rotator cuff repair by the senior author (S.S.B.) between January 1, 2000, and December 31, 2003, were reviewed. Patients were excluded from the study if their rotator cuff was repaired but there was not a subscapularis tear. Forty patients were included in this study. The median follow-up from the date of surgery to the last clinical evaluation was 5.0 years (range, 3.2 to 7.1 years). All patients had a complete history, physical examination, and plain radiographs of their shoulders. Both the modified University of California at Los Angeles (UCLA) and American Shoulder and Elbow Society (ASES) scores were calculated. RESULTS The visual analog scale for pain (mean +/- standard deviation) improved significantly (P < .001) from 6.1 +/- 2.4 preoperatively to 0.9 +/- 1.4 at the latest clinical follow-up evaluation; similarly, the mean modified ASES score improved significantly (P < .001) from 40.5 +/- 15.7 preoperatively to 91.2 +/- 12.7, and the mean modified UCLA score improved significantly (P < .001) from 15.7 +/- 4.2 preoperatively to 31.6 +/- 4.8. According to the UCLA scoring system, there were 18 excellent, 14 good, 6 fair, and 2 poor results. Eighty-three percent of patients returned to their usual work, sport, or hobbies after the operation. CONCLUSIONS At a median follow-up of 5 years, 80% (32 of 40) of patients had a good or excellent result after an arthroscopic subscapularis tendon repair. Eighty-eight percent of patients were satisfied with their shoulders at the latest follow-up evaluation. We conclude that the intermediate-term results show that arthroscopic subscapularis tendon repairs remain a good option for the treatment of patients with subscapularis tendon tears. LEVEL OF EVIDENCE Level IV, therapeutic case series.

Accuracy of Preoperative Magnetic Resonance Imaging in Predicting a Subscapularis Tendon Tear Based on Arthroscopy

PURPOSE The purpose of this study was to evaluate the diagnostic accuracy of magnetic resonance imaging (MRI) scan assessments of subscapularis tendon tears by comparing the preoperative MRI interpretations of radiologists with the actual results determined by arthroscopic evaluations of the same shoulders. METHODS This retrospective review comprised all 120 patients who underwent primary arthroscopic rotator cuff repairs performed by the senior author during 2006. Of the 120 patients, 90 had high-field strength, conventional MRI scans performed within 190 days before their arthroscopic procedures. RESULTS All 16 patients with preoperative MRI scans that were interpreted by the radiologists as positive for subscapularis tendon tears were confirmed to be positive by arthroscopy, resulting in perfect specificity. However, the radiologists diagnosed only 16 of 44 subscapularis tears (36%) identified by arthroscopy. This resulted in an overall sensitivity of 36%, specificity of 100%, positive predictive value of 100%, negative predictive value of 62%, and accuracy of 69%. CONCLUSIONS Preoperative MRI scans of the shoulder do not reliably predict which rotator cuff injury patients have subscapularis tendon tears. Subscapularis tendon tears that extend at least half the cephalad-to-caudal distance are more easily detected by MRI scans, whereas smaller tears are usually missed on MRI scans. LEVEL OF EVIDENCE Level III, development of diagnostic criteria with universally applied reference (nonconsecutive patients).

A Biomechanical Comparison of 2 Techniques of Footprint Reconstruction for Rotator Cuff Repair: The SwiveLock-FiberChain Construct Versus Standard Double-Row Repair

PURPOSE The purpose of this study was to compare the biomechanical fixation parameters of a standard double-row rotator cuff repair with those of a knotless footprint reconstruction using the double-row SwiveLock-FiberChain technique (Arthrex, Naples, FL). METHODS Seven matched pairs of human cadaveric shoulders were used for testing (mean age, 48 +/- 10.3 years). A shoulder from each matched pair was randomly selected to receive a standard 4-anchor double-row repair of the supraspinatus tendon, and the contralateral shoulder received a 4-anchor double-row SwiveLock-FiberChain repair. The tendon was cycled from 10 N to 100 N at 1 Hz for 500 cycles, followed by a single-cycle pull to failure at 33 mm/s. Yield load, ultimate load, cyclic displacement, and mode of failure were recorded. RESULTS Yield load and ultimate load were higher for the SwiveLock-FiberChain repair compared with the standard double-row repair for 6 of the 7 treatment pairs; however, 1 cadaver had a contrary outcome, so the overall mean differences in yield load and ultimate load were not significantly different from 0 by Student t test (P > .15). Furthermore, smaller differences between yield load and ultimate load for the SwiveLock-FiberChain repair in 5 of the 7 treatment pairs showed a self-reinforcing mechanism. CONCLUSIONS Double-row footprint reconstruction with the knotless SwiveLock-FiberChain system in this study had yield loads, ultimate loads, and cyclic displacements that were statistically equivalent to those of standard double-row rotation cuff reconstructions. CLINICAL RELEVANCE The SwiveLock-FiberChain systems combination of strength, self-reinforcement, and decreased operating time may offer advantages to the surgeon, particularly when dealing with older patients in whom poor tissue quality and total operative time are important considerations.

Associated Lesions Requiring Additional Surgical Treatment in Grade 3 Acromioclavicular Joint Dislocations

PURPOSE To evaluate the incidence of associated pathologic shoulder lesions that were addressed surgically in grade 3 acromioclavicular joint (ACJ) dislocations, as well as to compare this incidence between younger and older patients and between acute and chronic cases. METHODS In this multicenter nonrandomized retrospective study, 98 patients operated on for grade 3 ACJ dislocation underwent concomitant arthroscopic evaluation for the identification and treatment of any associated lesions. The type and treatment of associated lesions were collected in a central database and analyzed. We classified patients according to age (<45 years and ≥ 45 years) and according to the length of time between trauma and surgical treatment (≤ 30 days and ≥ 120 days), obtaining the following stratification: younger acute, older acute, younger chronic, and older chronic. RESULTS Of the patients, 42 (42.8%) were diagnosed with at least 1 additional pathologic lesion, and 29 (29.5%) required a dedicated additional treatment. Rates of treatment on associated lesions were analyzed: younger versus older groups presented a significant difference, as did younger acute versus older acute groups; SLAP and posterior rotator cuff tear treatments represented 24 of the 35 additional surgeries (68.5%). CONCLUSIONS The overall rate of associated pathologic lesions requiring additional surgical treatment in patients with ACJ dislocation was 29.5%. Patients aged 45 years or older had a greater risk of presenting with associated lesions that needed to be surgically addressed (odds ratio, 3.01). The overall rates of associated surgical lesions in acute versus chronic cases were not shown to be significantly different. LEVEL OF EVIDENCE Level IV, prognostic case series.

A systematic approach for diagnosing subscapularis tendon tears with preoperative magnetic resonance imaging scans.

PURPOSE To determine and propose a systematic approach to evaluating magnetic resonance imaging (MRI) scans for subscapularis tears and compares preoperative MRI interpretations with findings of the same shoulders at arthroscopy. METHODS The study was composed of 202 patients who underwent shoulder arthroscopy by 1 of 5 orthopaedic surgeons during a 3-month period. All patients had MRI scans performed within 6 months before arthroscopy. RESULTS Of the 202 patients, 82 had subscapularis tendon tears confirmed at the time of arthroscopy. The orthopaedic surgeons correctly diagnosed 60 of 82 patients (73%) with subscapularis tendon tears on preoperative MRI that were subsequently identified by arthroscopy. The orthopaedic surgeons correctly diagnosed 113 of 120 patients (94%) as not having subscapularis tendon tears. This resulted in an overall sensitivity of 73%, specificity of 94%, positive predictive value of 90%, negative predictive value of 84%, and accuracy of 86%. The frequency of subscapularis tears was highest when the long head of the biceps was displaced from the groove (88%), a combined supraspinatus/infraspinatus tear existed (71%), or the long head of the biceps tendon was torn (69%). CONCLUSIONS Preoperative MRI scans of the shoulder interpreted by orthopaedic surgeons with the described systematic approach resulted in improved accuracy in diagnosing subscapularis tendon tears compared with previous studies. A consistent finding is that larger subscapularis tendon tears are more easily detected using MRI scans whereas smaller tears are more frequently missed. LEVEL OF EVIDENCE Level III, development of diagnostic criteria with universally applied reference (nonconsecutive patients).

Arthroscopic Superior Capsular Reconstruction for Treatment of Massive Irreparable Rotator Cuff Tears

Massive irreparable rotator cuff tears have been troublesome entities to treat, especially in younger patients. Few good options exist, leaving most patients in recent years receiving a reverse total shoulder arthroplasty. Reverse shoulder arthroplasty carries serious risks, a limited lifespan, and no other viable options should it fail. Recent biomechanical studies have shown that the superior capsule is critical to containing the glenohumeral joint reduced, allowing the larger muscles like the deltoid and pectoralis major to function properly. The superior capsular reconstruction is an anatomic reconstruction of the superior capsule to restore the normal restraint to superior translation that occurs with a deficient rotator cuff. The technique described in this article is an arthroscopic reconstruction of the superior capsule with dermal allograft.

Pseudoparalysis From a Massive Rotator Cuff Tear Is Reliably Reversed With an Arthroscopic Rotator Cuff Repair in Patients Without Preoperative Glenohumeral Arthritis

Background: Pseudoparalysis is defined as active forward flexion less than 90° with full passive motion. There is controversy about the ideal surgical management of a massive rotator cuff tear with pseudoparalysis. Purpose/Hypothesis: The purpose of this study was to prospectively analyze the ability to reverse pseudoparalysis with an arthroscopic rotator cuff repair (ARCR). The hypothesis was that in the absence of substantial glenohumeral arthritis, preoperative fatty infiltration of grade 3 or higher and an acromiohumeral interval (AHI) of less than 7 mm would not prevent reversal of pseudoparalysis with an ARCR. Study Design: Case series; Level of evidence, 4. Methods: A prospective multicenter study of ARCR performed for preoperative pseudoparalysis was conducted. The minimum follow-up was 1 year. The mean patient age was 63 years, and pseudoparalysis was present for a mean of 4.2 months preoperatively. Preoperative radiographic evaluation included plain film evaluation of the AHI and Hamada classification and MRI evaluation of fatty degeneration and rotator cuff retraction. Functional outcome was determined by the Simple Shoulder Test (SST), American Shoulder and Elbow Surgeons (ASES) Shoulder Score, visual analog scale (VAS), and subjective shoulder value (SSV). Results: Of the 58 patients enrolled, 56 had at least 1 year of follow-up. Mean active forward flexion improved from 47° preoperatively to 159° postoperatively (P < .001). Statistically significant improvements were seen in the SST (from 2.8 preoperatively to 10.1 postoperatively), SSV (from 28 to 83), ASES Shoulder Score (from 37 to 88), and VAS (from 5.7 to 1.1) (P < .001). Pseudoparalysis was reversed in 53 of 56 patients (95%). There was no difference in the rate of reversal of pseudoparalysis between those patients with an AHI of less than 7 mm (88.2%) and those with an AHI of 7 mm or more (96.9%) (P =.289). Pseudoparalysis was reversed in all 8 of the patients with fatty degeneration of grade 3 or higher in 1 or more of the rotator cuff muscles. Conclusion: ARCR can lead to reversal of preoperative pseudoparalysis in patients with minimal preoperative glenohumeral arthritis. ARCR is a viable first line of treatment for patients with pseudoparalysis in the absence of advanced glenohumeral arthritis.

The anterior borders of the clavicle and the acromion are not always aligned in the intact acromioclavicular joint: a cadaveric study

BACKGROUND The aim of this study was to find reliable anatomic landmarks of the normal acromioclavicular joint (ACJ) that could enable the precise evaluation of the horizontal displacement of the clavicle after dislocation. The hypothesis was that the anterior borders of the acromion and the clavicle are always aligned in intact ACJs. MATERIALS AND METHODS In 30 cadaveric specimens, the anterior and posterior borders of the ACJs articular facets and the most prominent anterior and posterior bony landmarks of the acromion and the clavicle were identified. The anterior and posterior overhang of the acromion and the clavicle was measured in relation to the borders of the articular facets. Therefore, the possible anterior and posterior alignment of the ACJ was evaluated. RESULTS Anteriorly, only 18 ACJs (60%) were aligned whereas 7 (24%) had major overhang of the acromion and 3 (10%) had major overhang of the clavicle. Similarly, 18 cases (60%) were posteriorly aligned, whereas 6 (20%) had major clavicular overhang and 4 (14%) had major overhang of the acromion. In 78% of these cases, the ACJ was aligned as well anteriorly as posteriorly (P < .001). Finally, the larger the width of the acromion (P = .032) or the clavicle (P = .049), the better the posterior joint alignment. CONCLUSION Our hypothesis was not verified. The acromion and clavicle are not perfectly aligned in a significant number of specimens with intact ACJs (40% of cases). The most reliable landmarks remain their articular facets.

Middle Glenohumeral Ligament Abrasion Causing Upper Subscapularis Tear

The middle glenohumeral ligament (MGHL) typically contributes partially to the anterior stability of the shoulder. In a very limited number of cases, the MGHL can cause abrasion on the upper edge of the subscapularis causing persistent pain symptoms for patients. The condition is exacerbated by internal rotation of the arm. In this Technical Note, we describe this entity and call it the SAM lesion (Subscapularis Abrasion from the MGHL). We present a technique of addressing this lesion.