James S. Kercher

Clinical Cartilage Restoration: Evolution and Overview

BackgroundClinical cartilage restoration is evolving, with established and emerging technologies. Randomized, prospective studies with adequate power comparing the myriad of surgical techniques used to treat chondral injuries are still lacking and it remains a challenge for the surgeon treating patients to make evidence-based decisions. Questions/purposesWe reviewed the history of the major cartilage repair/restorative procedures, indications for currently available repair/restorative procedures, and postoperative management.MethodsWe performed searches using MEDLINE and cartilage-specific key words to identify all English-language literature. Articles were selected based on their contributions to our current understanding of the basic science and clinical treatment of articular cartilage lesions or historical importance. We then selected 77 articles, two of which are articles of historical importance. ResultsCurrent cartilage restorative techniques include débridement, microfracture, osteochondral fragment repair, osteochondral allograft, osteochondral autograft, and autologous chondrocyte transplantation. Pending techniques include two-staged cell-based therapies integrated into a variety of scaffolds, single-stage cell-based therapy, and augmentation of marrow stimulation, each with suggested indications including lesion size, location, and activity demands of the patient. The literature demonstrates variable improvements in pain and function contingent upon multiple variables including indications and application.ConclusionsFor the patient with symptomatic chondral injury, numerous techniques are available to the surgeon to relieve pain and improve function. Until rigorous clinical trials (prospective, adequately powered, randomized control) are available, treatment decisions should be guided by expert extrapolation of the available literature based in historically sound principles.

Rotator cuff repair augmentation using a novel polycarbonate polyurethane patch: preliminary results at 12 months’ follow-up

BACKGROUND Preventing anatomic failure after rotator cuff repair (RCR) remains a challenge. Augmentation with a surgical mesh may permanently reinforce the repair and decrease failure rates. The purpose of this study is to assess the postoperative outcomes of open RCR augmented with a novel reticulated polycarbonate polyurethane patch. MATERIALS AND METHODS Ten patients with supraspinatus tendon tears underwent open RCR augmented with a polycarbonate polyurethane patch secured in a 6-point fixation construct placed over the repaired tendon. Patients were evaluated with preoperative and postoperative outcome measures, including the Simple Shoulder Test, visual analog pain scale, American Shoulder and Elbow Surgeons shoulder score, Cumulative Activities of Daily Living score, and University of California, Los Angeles shoulder scale, as well as range of motion. Postoperative magnetic resonance imaging was used to evaluate repair status. RESULTS Patients showed significant improvements in visual analog pain scale, Simple Shoulder Test, and American Shoulder and Elbow Surgeons shoulder scores at both 6 and 12 months postoperatively (P < .05 and P < .01, respectively). The University of California, Los Angeles postoperative score was good to excellent in 7 patients at 6 months and in 8 patients at 12 months. Range of motion in forward flexion, abduction, internal rotation, and external rotation was significantly improved at both 6 and 12 months postoperatively (P < .05 and P < .01, respectively). Magnetic resonance imaging at 12 months showed healing in 90%; one patient had a definitive persistent tear. We found no adverse events associated with the patch, including the absence of fibrosis, mechanical symptoms, or visible subacromial adhesions. DISCUSSION The polycarbonate polyurethane patch was designed to support tissue in growth and enhance healing as shown by preclinical animal studies. Clinically, the patch is well tolerated and shows promising efficacy, with a 10% retear rate at the 12-month time point.

The arthroscopic management of partial-thickness rotator cuff tears: A systematic review of the literature

PURPOSE There is currently limited information available in the orthopaedic surgery literature regarding the appropriate management of symptomatic partial-thickness rotator cuff tears. METHODS A systematic search was performed in PubMed, EMBASE, CINAHL (Cumulative Index to Nursing and Allied Health Literature), and the Cochrane Central Register of Controlled Trials of all published literature pertaining to the arthroscopic management of partial-thickness rotator cuff tears. Inclusion criteria were all studies that reported clinical outcomes after arthroscopic treatment of both articular-sided and bursal-sided lesions using a validated outcome scoring system and a minimum of 12 months of follow-up. Data abstracted from the selected studies included tear type and location (articular v bursal sided), treatment approach, postoperative rehabilitation protocol, outcome scores, patient satisfaction, and postoperative imaging results. RESULTS Sixteen studies met the inclusion criteria and were included for the final analysis. Seven of the studies treated partial-thickness rotator cuff tears with debridement with or without an associated subacromial decompression, 3 performed a takedown and repair, 5 used a transtendon repair technique, and 1 used a transosseous repair method. Among the 16 studies reviewed, excellent postoperative outcomes were reported in 28.7% to 93% of patients treated. In all 12 studies with available preoperative baseline data, treatment resulted in significant improvement in shoulder symptoms and function. For high-grade lesions, the data support arthroscopic takedown and repair, transtendon repairs, and transosseous repairs, with all 3 techniques providing a high percentage of excellent results. Debridement of partial-thickness tears of less than 50% of the tendons thickness with or without a concomitant acromioplasty also results in good to excellent surgical outcomes; however, a 6.5% to 34.6% incidence of progression to full-thickness tears is present. CONCLUSIONS This systematic review of 16 clinical studies showed that significant variation is present in the results obtained after the arthroscopic management of partial-thickness rotator cuff tears. What can be supported by the available data is that tears that involve less than 50% of the tendon can be treated with good results by debridement of the tendon with or without a formal acromioplasty, although subsequent tear progression may occur. When the tear is greater than 50%, surgical intervention focusing on repair has been successful. There is no evidence to suggest a differential in outcome for tear completion and repair versus transtendon repair of these lesions because both methods have been shown to result in favorable outcomes. LEVEL OF EVIDENCE Level IV, systematic review of Level IV studies.

Augmentation Strategies following the Microfracture Technique for Repair of Focal Chondral Defects.

The operative management of focal chondral lesions continues to be problematic for the treating orthopedic surgeon secondary to the limited regenerative capacity of articular cartilage. Although many treatment options are currently available, none fulfills the criteria for an ideal repair solution, including a hyaline repair tissue that completely fills the defect and integrates well with the surrounding normal cartilage. The microfracture technique is an often-utilized, first-line treatment modality for chondral lesions within the knee, resulting in the formation of a fibrocartilaginous repair tissue with inferior biochemical and biomechanical properties compared to normal hyaline cartilage. Although symptomatic improvement has been shown in the short term, concerns about the durability and longevity of the fibrocartilaginous repair have been raised. In response, a number of strategies and techniques for augmentation of the first-generation microfracture procedure have been introduced in an effort to improve repair tissue characteristics and reduce long-term deterioration. Recent experimental approaches utilize modern tissue-engineering technologies including local supplementation of chondrogenic growth factors, hyaluronic acid, or cytokine modulation. Other second-generation microfracture-based techniques use different types of scaffold-guided in situ chondroinduction. The current article presents a comprehensive overview of both the experimental and early clinical results of these developing microfracture augmentation techniques.

Effect of Interference Screw Depth on Fixation Strength in Biceps Tenodesis

PURPOSE The purpose of this study was to assess the biomechanical performance of the long head of the biceps tenodesis with an interference screw with respect to screw depth. METHODS Twenty-one human cadaveric shoulders were randomized into 3 treatment groups (7 each): interference screw placed flush to the humeral cortex, 50% proud, or fully recessed. Bone density was determined, and subpectoral biceps tenodesis was performed with 8 × 12 mm Bio-Tenodesis screws (Arthrex, Naples, FL). Each construct was cyclically loaded from 5 to 70 N for 500 cycles at 1 Hz and then pulled to failure at 1 mm/s. Relative actuator displacement was calculated from cyclic testing. Maximum load, elongation, linear stiffness, and failure mode were recorded from pull-to-failure testing. Because of numerous failures during cyclic testing, the final load data from the fully recessed group were not statistically analyzed. The remaining groups were compared by use of a 2-tailed, Student unpaired t test and χ(2) analysis. RESULTS There was no significant difference in displacement among groups during cyclic testing. Five specimens in the recessed group failed during cyclic testing, whereas 2 specimens and 0 specimens failed in the proud and flush groups, respectively. The maximum loads sustained were 281.6 ± 77.8 N, 184.5 ± 56.3 N, and 209.1 ± 57.0 N for the flush group, 50% proud group, and recessed group (in those specimens surviving cyclical loading), respectively. CONCLUSIONS Placement of a Bio-Tenodesis screw flush to the humeral cortex is preferred for maximum fixation strength in subpectoral biceps tenodesis. A screw placed to 50% depth may be effective in the laboratory setting, but recessed placement is more variable and requires additional fixation. The fully recessed group resulted in 5 of 7 failures during cyclical loading, with no specimens failing in the flush group. CLINICAL RELEVANCE This study shows the importance of determining the optimal depth of interference screw placement during biceps tenodesis to obtain optimal biomechanical performance and reduce the risk of fixation failure.

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.

Special Issue on Microfracture

Articular cartilage injuries are common and have been found in approximately 60% of knees1,2 and 5% of shoulders3 undergoing arthroscopy. While many of these are incidental findings, the remainder are often symptomatic and debilitating and present a unique challenge secondary to the poor regenerative capacity of the native tissue. Cartilage repair procedures play an integral role in the treatment of these injuries and serve as a therapeutic bridge between debridement and arthroplasty. Technology is rapidly advancing, and emerging treatments have evolved to include minced autologous cartilage, minced juvenile allograft cartilage, scaffolds, and cell-infused matrices; however, tissue durability and outcomes of these procedures have yet to be defined. Despite the developments, the most tried and true treatment for cartilage injury is microfracture. This technique, which was developed and first described by Steadman in 1999,4 is the most common reparative procedure performed in the United States with over 25,000 cases annually.5 By some estimates, more than 100,000 microfracture procedures are performed annually. Appropriately, this issue is dedicated to this procedure. Microfracture is a time-tested technique that has consistently demonstrated improved outcomes in the treatment of symptomatic cartilage defects in the knee6 and is now showing promise in the shoulder7 and hip8 as well. Dr. Richard Steadman is credited for his visionary thinking and deserves credit for this foresight. His commitment to clinical follow-up, the basic science that has furthered our surgical techniques, and the commitment of others who are now reporting their outcomes have led microfracture to become the comparator to emerging technologies. Those of us who treat these patients are indebted for his contribution.

Anteromedial Tibial Tubercle Osteotomy (Fulkerson Osteotomy)

Multiple case series have reported outcomes of the AMZ procedures. Despite the heterogeneity in outcome measurements, results demonstrate high percentages of excellent and good results and improvements in objective, subjective and functional measures. Attention to details related to surgical planning and properly managing patient expectations is most likely to lead to good or excellent results. Newer techniques (i.e., the T3 system) allow the surgeon to objectively determine the inclination of the osteotomy to properly restore patellofemoral mechanics based upon the preoperative planning.