A Radiographic Sizing Algorithm for Tibial Plateau Osteochondral Allografts

OBJECTIVE

Tibial plateau osteochondral allograft transplantation is a promising treatment for symptomatic chondral damage of the proximal tibia due to a variety of etiologies. The purpose of this investigation is to develop an accurate and reproducible algorithm for sizing tibial plateau allografts based on recipient radiographs.

DESIGN

A cadaveric study was performed in which radiographs of 10 fresh frozen cadaveric knees were compared to measured digital photographs of the disarticulated specimens. By comparing the average distance between standard anatomical landmarks on the radiographs to the gross specimens, a correlation factor was calculated that could be applied to recipient radiograph measurements for more accurate sizing of tibial plateau allografts.

RESULTS

In the coronal plane there were no differences between the mean radiographic and mean morphologic measurements of either the medial or lateral tibial plateau. However, in the sagittal plane the anatomic specimens of the medial and lateral plateau were 90% and 80%, respectively, of the measurements made from the lateral radiograph.

CONCLUSIONS

This cadaveric investigation is the first to propose a sizing algorithm for tibial plateau osteochondral allografts. Based on the results, an anteroposterior radiograph can reliably measure the width of both the medial and lateral tibial plateau without any correction needed. The average morphological lengths of the medial and lateral tibial plateau, on the other hand, were found to be 90% and 80%, respectively, of the radiographically measured lengths. Without correction, this would lead to the implantation of oversized grafts that may contribute to early failure.

A Hybrid Transtibial Technique Combines the Advantages of Anteromedial Portal and Transtibial Approaches: A Prospective Randomized Controlled Trial

BACKGROUND

The anteromedial (AM) portal and transtibial (TT) approaches are 2 common anterior cruciate ligament (ACL) femoral tunnel drilling techniques, each with unique benefits and disadvantages. A hybrid TT (HTT) technique using medial portal guidance of a flexible TT guide wire has recently been described that may combine the strengths of both the AM portal and the TT approaches.

HYPOTHESIS

The HTT technique will achieve anatomic femoral tunnel apertures similar to the AM portal technique, with improved femoral tunnel length and orientation.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 2.

METHODS

A total of 30 consecutive patients with primary ACL tears were randomized to undergo the TT, AM portal, or HTT technique for femoral tunnel positioning at the time of reconstruction. All patients underwent 3-dimensional computed tomography of the operative knee at 6 weeks postoperatively. Femoral and tibial tunnel aperture positions and tunnel lengths, as well as graft bending angles in the sagittal and coronal planes, were measured.

RESULTS

Tibial tunnel lengths and aperture positions were identical between the 3 groups. The AM portal and HTT techniques achieved identical femoral aperture positions in regard to both height (P = .629) and depth (P = .582). By contrast, compared with the AM portal and HTT techniques, femoral apertures created with the TT technique were significantly higher (P < .001 and P < .001, respectively) and shallower (P = .014 and P = .022, respectively) in the notch. The mean femoral tunnel length varied significantly between the groups, measuring 35.2, 41.6, and 54.1 mm for the AM portal, HTT, and TT groups, respectively (P < .001). Last, there was no difference between the mean coronal (P = .190) and sagittal (P = .358) graft bending angles between the TT and HTT groups. By contrast, compared with the TT and HTT techniques, femoral tunnels created with the AM portal technique were significantly more angulated in the coronal plane (17.7° [P < .001] and 12.5° [P = .006], respectively) and sagittal plane (13.5° [P < .001] and 10.5° [P = .013], respectively).

CONCLUSION

This prospective randomized controlled trial found that the HTT technique achieved femoral aperture positions equally as anatomic as the AM portal technique but produced longer, less angulated femoral tunnels, which may help reduce graft strain and mismatch. As such, this hybrid approach may represent a beneficial combination of both the TT and the AM portal techniques.

REGISTRATION

NCT02795247 (ClinicalTrials.gov identifier).

Biomechanical Evaluation of an All-Inside Posterior Medial Meniscal Root Repair Technique Via Suture Fixation to the Posterior Cruciate Ligament

PURPOSE

To evaluate the tibiofemoral contact mechanics of an all-inside posterior medial meniscal root repair technique via suture fixation to the posterior cruciate ligament (PCL) and to compare with that of the intact knee and the knee with a root tear.

METHODS

Tibiofemoral contact mechanics were recorded in 8 human cadaveric knee specimens using pressure sensors. Each knee underwent 3 testing conditions related to the posterior medial meniscal root: (1) intact knee; (2) root tear; and (3) all-inside repair via suture fixation to the PCL. Knees were loaded with a 1000-N axial compressive force at 4 knee flexion angles (0°, 30°, 60°, 90°). Calculations were performed for contact area, mean contact pressure, and peak contact pressure. A generalized linear model with a Tukey adjusted least square means test was used to determine differences between testing conditions.

RESULTS

Across all knee flexion angles, there was an overall mean 26.3% reduction in contact area with root tear (211.34 mm² vs intact 286.64 mm², P = .0002), and a 31.6% increase from root tear to repair (277.61 mm², P = .0297). Across all knee flexion angles, there was an overall mean 24.3% increase in contact pressure with root tear (1849.12 N/mm² vs. intact 1487.52 N/mm², P < .0001), and a 31.1% decrease from root tear to repair (1410.7 N/mm², P = .0037). Across all knee flexion angles, there was an overall mean 10.6% increase in peak contact pressure with root tear (4083.55 N/mm² vs. intact 3693.68 N/mm², P < .0001), and a 12.4% decrease from root tear to repair (3632.13 N/mm², P = .531).

CONCLUSIONS

In most testing conditions and with overall averaging across knee flexion angles, the all-inside posterior medial meniscal root repair with suture fixation to the adjacent PCL fibers restored contact area (from 26.3% reduction with root tear to 31.6% increase with repair), contact pressures (from 24.3% increase with root tear to 31.1% decrease with repair), and peak contact pressures (from 10.6% increase with root tear to 12.4% decrease with repair) to that of the intact knee This may be a future potential technique to limit complications associated with the traditional transtibial pull-out method of repair.

CLINICAL RELEVANCE

This technique may provide a posterior medial meniscal root repair construct that restores most tibiofemoral contact mechanics and offers theoretical benefits of technical ease and potential for an acceptable, less "anatomic" repair location.

Management of Isolated Capitate Nonunion: A Case Series and Literature Review

Background  Isolated capitate nonunion is rare. No consensus on the appropriate treatment for this condition exists. Case Description  We reported two cases of capitate fracture nonunion presenting several months after untreated high-impact wrist trauma. Treatment was delayed as both patients' nonunions were missed on conventional radiographs. Both were ultimately diagnosed with advanced imaging and successfully treated with internal fixation and autogenous bone grafting. The relevant literature pertaining to capitate nonunion was reviewed. Literature Review  Immobilization and internal fixation with bone grafting for capitate nonunion have been described in the literature. Loss of vascular supply and progression to avascular necrosis is a concern after capitate nonunion. Clinical Relevance  We present two cases and review the literature on the diagnosis and treatment of this rare injury to guide management. Internal fixation with autogenous bone grafting could play a role in management for this rare condition.

Long Head of Biceps Tendon Management: a Survey of the American Shoulder and Elbow Surgeons

BACKGROUND

Management of symptomatic long head of biceps tendon (LHBT) pathology remains a source of debate.

QUESTIONS/PURPOSES

The purpose of this study was to identify consensus trends for the treatment of LHBT pathology among specialists.

METHODS

A survey was distributed to members of the American Shoulder and Elbow Society (ASES), consisting of three sections-demographics, case scenarios, and general LHBT pathology management. Cases presented common clinical scenarios, and surgeons reported their management preferences. Consensus responses were defined as > 50% of participants giving a single response.

RESULTS

One hundred and forty-two of 417 (34%) surgeons completed surveys. Forty-seven percent of questions reached a consensus answer. Biceps tenodesis was the overwhelmingly preferred technique in cases demonstrating LHBT pathology, as compared to tenotomy. No consensus, however, was reached regarding a specific surgical technique for biceps tenodesis. The two most popular techniques were arthroscopic tenodesis to bone and open subpectoral biceps tenodesis. Fellowship-trained arthroscopic surgeons and surgeons with a largely arthroscopic practice were more likely to perform tenodesis arthroscopically.

CONCLUSION

ASES members favored biceps tenodesis over tenotomy for surgical management of LHBT pathology, without consensus regarding a specific surgical technique.

Subscapularis tendon loading during activities of daily living

BACKGROUND

The purpose of this study was to determine the relative amount of load that is transmitted through the superior portion of the subscapularis during activities of daily living as compared with the load that is transmitted through the middle and inferior portions in a normal shoulder and in a shoulder with a supraspinatus tear.

METHODS

By use of the Newcastle shoulder model, the subscapularis was modeled with 3 lines of action encircling the humeral head. The load was measured in the entire subscapularis, and the percentage of this load in each of the 3 tendinous bands was calculated. Subsequently, a supraspinatus tear was simulated, and the forces generated by the subscapularis and glenohumeral joint contact forces were measured.

RESULTS

The maximum force produced by the entire subscapularis muscle for the various activities ranged from 3 to 43 N. Load sharing between the 3 subscapularis bands showed that the superior band bore the largest percentage of the total load of the muscle (95% ± 2%). The load in the subscapularis, particularly in the superior band, increased significantly when a supraspinatus tear was simulated (P < .0001).

CONCLUSION

The superior band of the subscapularis tendon bears the highest percentage of load compared with the middle or inferior band. The load in the subscapularis increased significantly in the presence of a simulated supraspinatus tear. Because a disproportionate amount of force is transmitted through the superior subscapularis, more clinical research is warranted to determine whether tears in this region should be routinely repaired.

Evaluation and treatment of internal impingement of the shoulder in overhead athletes

One of the most common pathologic processes seen in overhead throwing athletes is posterior shoulder pain resulting from internal impingement. “Internal impingement” is a term used to describe a constellation of symptoms which result from the greater tuberosity of the humerus and the articular surface of the rotator cuff abutting the posterosuperior glenoid when the shoulder is in an abducted and externally rotated position. The pathophysiology in symptomatic internal impingement is multifactorial, involving physiologic shoulder remodeling, posterior capsular contracture, and scapular dyskinesis. Throwers with internal impingement may complain of shoulder stiffness or the need for a prolonged warm-up, decline in performance, or posterior shoulder pain. On physical examination, patients will demonstrate limited internal rotation and posterior shoulder pain with a posterior impingement test. Common imaging findings include the classic “Bennett lesion” on radiographs, as well as articular-sided partial rotator cuff tears and concomitant SLAP lesions. Mainstays of treatment include intense non-operative management focusing on rest and stretching protocols focusing on the posterior capsule. Operative management is variable depending on the exact pathology, but largely consists of rotator cuff debridement. Outcomes of operative treatment have been mixed, therefore intense non-operative treatment should remain the focus of treatment.

All-Arthroscopic Modified Rotator Interval Slide for Massive Anterosuperior Cuff Tears Using the Subdeltoid Space: Surgical Technique and Early Results

BACKGROUND

Traditional intra-articular arthroscopic repair techniques for massive anterosuperior rotator cuff tears are technically demanding and necessitate sacrifice of the rotator interval to enable visualization. An interval slide allows mobilization through release of the medial aspect of the rotator interval, while leaving the lateral, bridging fibers intact.

QUESTIONS/PURPOSES

The purpose of this study was to report a novel, arthroscopic, open-equivalent technique using the subdeltoid space to address these tears along with early clinical results.

METHODS

A retrospective review of prospectively collected data identified 11 consecutive arthroscopic massive anterosuperior rotator cuff repairs with a concomitant biceps tenodesis performed by the senior surgeon using a uniform technique. Outcome measures included range of motion, visual analog scale for pain, rotator cuff strength, American Shoulder and Elbow Surgeons (ASES) outcome scale, and Short Form-12 (SF-12).

RESULTS

Average length of follow-up was 22.2 months (range 12.5-30.0 months). Visual analog scale (VAS) pain scores, ASES, and SF-12 all demonstrated significant improvement from pre-op to final follow-up from 6.2 to 0.9 (p < 0.05), 27.4 to 82.8 (p < 0.05), and 26.6 to 45.5 (p < 0.05) respectively. Average forward flexion improved from 145° to 160° (p < 0.05). Seven of the nine patients with a positive preoperative belly press had a negative test at final follow-up. Nine of the 10 patients with a positive lift off test demonstrated a negative test on final follow-up. Ninety-one percent reported they were satisfied with their outcome.

CONCLUSIONS

The described modified all-arthroscopic subdeltoid approach for anterosuperior cuff repairs enabled an open-equivalent interval slide technique that preserved the bridging lateral fibers of the rotator interval and demonstrated promising early-term clinical results.

Single-Incision Technique for Repair of Distal Biceps Tendon Avulsions With Intramedullary Cortical Button

Patients who experience distal biceps tendon avulsions generally benefit from surgical intervention. Compared with nonoperative treatment, surgery has shown improved muscle endurance as well as increased flexion and supination strength. Although a number of surgical techniques exist, repair of the distal biceps through a single incision is gaining popularity. This may be due in part to patient preference and emerging technologies such as cortical button fixation, suture anchors, and intraosseous screws. In this report, we present a simple technique for anatomically repairing distal biceps injuries using an intramedullary tenodesis button. This technique has the benefit of using a single unicortical drill hole in the radius while allowing the surgeon to sequentially tighten the tendon to its desired level of tension. When appropriate surgical steps are followed, it can be completed in a reliable, safe, and efficient manner through a single incision.

Long-Term Evaluation of Autologous Chondrocyte Implantation: Minimum 7-Year Follow-Up

PURPOSE

The purpose of this study was to report the clinical outcomes of autologous chondrocyte implantation (ACI) procedures performed by a single orthopedic surgeon at a minimum of 7 years follow-up.

METHODS

A retrospective review of prospectively collected data was performed on 29 patients who underwent ACI of the knee between the years of 1998 and 2003. Prospective data were collected to assess changes in standardized outcome measures preoperatively and 2, 4, and 7 years postoperatively. All patients enrolled in the study were also recruited to undergo physical examination when possible.

RESULTS

The final cohort consisted of 29 patients with a mean final follow-up time of 8.40 years (range = 7.14-10.88 years). Comparing preoperative scores to 7-year postoperative values, the mean International Knee Documentation Committee (IKDC) score improved from 39.80 to 59.24 (P < 0.001), mean Tegner-Lysholm score increased from 48.07 to 74.17 (P < 0.001), SF-12 physical score improved from 40.38 to 48.66 (P < 0.001), and SF-12 mental score improved from 44.14 to 48.98 (P < 0.05). Significant improvement occurred in Knee Injury and Osteoarthritis Outcome Score (KOOS) pain (56.03 to 80.36), symptoms (54.19 to 74.75), activities of daily living (72.01 to 85.90), sports (23.34 to 55.34), and quality of life (24.56 to 56.03) (P < 0.001). In addition, 7-year postoperative scores were at or near levels seen at 2 years (mean = 2.16; range = 0.94-4.03 years) and 4 years (mean = 4.43; range = 2.16-5.88 years) postoperatively, reflecting durable improvement. Subjectively, on a scale of 1 to 10 (10 being completely satisfied), the mean postoperative satisfaction rate was 8.14. Additionally, 88.9% of the patients would elect to have this surgery again if the same problem was to occur in the contralateral joint.

CONCLUSIONS

The results of ACI in patients who present with symptomatic, full-thickness chondral defects remain durable at a minimum of 7-year follow-up with persistent, high levels of patient satisfaction.

LEVEL OF EVIDENCE

Case series; Level of evidence, IV.