Systematic Review of Complications Associated With Proximal Hamstring Tendon Repair.

Background: Although several complications of proximal hamstring tendon ruptures have been reported in the literature, few studies have comprehensively analyzed the complication profile of proximal hamstring tendon repair. Purpose: To identify the overall rate of complications following proximal hamstring tendon repair and to differentiate these complications into categories. Study Design: Systematic review; Level of evidence, 4. Methods: Included in this review were studies that examined surgical repair of proximal hamstring tendon ruptures; all studies were in English and had an evidence level of 4 or higher. No restrictions were made regarding publication date or methodological quality. Data regarding complications were extracted to calculate the overall complication rate as well as the rate of major and minor complications. A quantitative data synthesis was conducted using the chi-square test to compare the proportion of patients who experienced complications with the endoscopic versus open approach. Results: A total of 43 articles including 2833 proximal hamstring tendon repairs were identified. The overall postoperative complication rate was 15.3% (n = 433). The rate of major complications was 4.6%, including a 1.7% rate of sciatic nerve injury, 0.8% rate of venous thromboembolism, 0.8% reoperation rate, 0.8% rerupture rate, and 0.4% rate of deep infection. Minor complications included a 2.4% rate of posterior femoral cutaneous nerve injury, 2.3% rate of persistent hamstring myopathy, 2.2% rate of persistent sitting pain, 1.8% rate of peri-incisional numbness, 1.1% rate of superficial infection, and 0.8% rate of hematoma/seroma. Conclusion: Proximal hamstring tendon repair is associated with an overall complication rate of 15.3%, including a 4.6% rate of major complications.

Graft Augmentation of Rotator Cuff Repair Improves Load to Failure But Does Not Affect Stiffness or Gap Formation: A Meta-analysis of Biomechanical Studies.

PURPOSE: To examine the biomechanical properties of rotator cuff repair with graft augmentation (RCR-G) with regard to ultimate load to failure, gap displacement, and stiffness. METHODS: A systematic review was performed by searching PubMed, the Cochrane library, and Embase using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to identify studies that analyzed the biomechanical properties of RCR-G. The search string implemented used the concepts "rotator cuff" and "graft," and "biomechanical" OR "cadaver." Meta-analysis was performed to provide a quantitative comparison of the 2 techniques. Primary outcome measures were ultimate load to failure (N), gap displacement (mm), and stiffness (N/mm). RESULTS: Our initial search yielded 1,493 articles for review. Following screening for inclusion criteria, 8 studies were included in the meta-analysis, including a total of 191 cadaveric specimens (106 RCR-G, 85 RCR). The pooled analysis from 6 studies reporting on ultimate load to failure revealed a statistically significant difference in favor of RCR-G compared with RCR (P < .001). Pooled analysis from 6 studies reporting on gap displacement failed to reveal a difference between RCR-G and RCR (P = .719). Pooled analysis from 4 studies reporting on stiffness failed to reveal a difference between RCR-G and RCR (P = .842). CONCLUSIONS: Graft augmentation of RCR in vitro resulted in significantly increased ultimate load to failure, with no influence on gap formation or stiffness. CLINICAL RELEVANCE: The biomechanical advantage of RCR with graft augmentation demonstrated via increased ultimate load to failure in cadaveric studies may provide an explanation for the decreased RCR retear rates and improved patient reported outcomes reported in the clinical literature regarding graft augmentation.

The Posterior Femoral Cutaneous Nerve and Branches are in Proximity to the Surgical Approach During Proximal Hamstring Repair.

Purpose: The purpose of our study is to identify the location of the posterior femoral cutaneous nerve (PFCN) and its branches in relation to the proximal hamstring tendon. Methods: Fifteen lower torso human cadaveric specimens were dissected in prone position. Skin and subcutaneous tissues were reflected to expose the gluteal and hamstring musculature. The distance between the ischial tuberosity and lateral border of the hamstring, PFCN, perineal branch of the PFCN, and descending femoral branch of the PFCN was measured with digital calipers. Measurements were repeated three times and averaged. Results: The PFCN was 30.5 ± 11.4 mm lateral to the central tip of the ischial tuberosity (range: 15.7 to 52.0 mm). The average longitudinal distance from the tip of the ischial tuberosity to the point where the perineal branch crossed the hamstrings was 24.1 ± 15.0 mm (range: 9.9 to 52.2 mm). The average longitudinal distance to the point where the descending cutaneous branch crossed the hamstrings was 83.3 ± 21.3 mm (range: 41.3 to 110.3 mm). The PFCN was nearest to the inferior border of the gluteus maximus 45.8 ± 13.6 mm lateral to the ischial tuberosity (range: 13.6 to 62.1 mm). Eleven specimens (73%) had one identifiable perineal branch; four (27%) had two distinct perineal branches. Conclusions: The PFCN was in close proximity to the surgical approach used during proximal hamstring repair, with the perineal branch consistently crossing the surgical field transversely. The location of these nerves varied substantially among the specimens tested, with some nerves less than 1 cm from the ischial tuberosity and 27% of specimens with two perineal branches.

Postoperative Rehabilitation of Posterior Cruciate Ligament Surgery: A Systematic Review.

Posterior cruciate ligament (PCL) injuries can be debilitating knee injuries, having involvement in up to 44% of traumatic knee injuries. However, isolated PCL injuries are relatively infrequent. Therefore, effective evidence-based rehabilitation protocols have proven to be elusive. This systematic review aims to summarize the latest evidence on postoperative rehabilitation protocols for patients undergoing PCL reconstruction. Studies included in this paper included those published from 1991 to 2019 with a grade 1 to 5 level of evidence discussing the postoperative PCL rehabilitation. A multidatabase search using largely PubMed and Ovid was conducted using relevant keywords such as "PCL," "postoperative," and "rehabilitation," initially leading to 955 papers, which were narrowed by relevance to 12 final published studies used in the analysis. Through careful review of the evidence, crucial principles of rehabilitation, such as an initial focus on protecting the graft during strengthening, as well as an optimized PCL reconstruction protocol are presented here. Rehabilitation following PCL reconstruction continues to be limited by a lack of high-quality evidence-based publications.

Evaluation of Risk to the Suprascapular Nerve During Arthroscopic SLAP Repair: Is a Posterior Portal Safer?

PURPOSE: The purpose of this study was to compare the risk of glenoid perforation during SLAP repair for suture anchors placed through an anterolateral portal versus a posterolateral portal of Wilmington. METHODS: Ten bilateral cadaveric shoulders were randomized to suture anchor placement through an anterolateral portal on one shoulder and a posterolateral portal on the contralateral shoulder. Anchors were placed into anterior, posterior, and far posterior positions on the glenoid rim (1 o'clock, 11 o'clock, and 10 o'clock positions for right shoulders). The shoulder was then dissected, and the distance from the suture anchor tip to the nerve was measured if perforation occurred. The maximum load and failure mechanism of each anchor was assessed with a materials testing system machine. RESULTS: Only 2 of 20 anchors placed in the posterosuperior glenoid through the posterolateral portal perforated compared with 16 of 20 of the anchors placed through the anterolateral portal (P < .05). The mean distance from the perforated anchor tip to the suprascapular nerve was 2.5 ± 1.4 mm for the anterolateral portal and 4.4 ± 0.6 mm for the posterolateral portal (P = .18). We did not observe a significant difference in biomechanical strength (P > .05). CONCLUSIONS: There is a high rate of glenoid perforation in close proximity to the suprascapular nerve when placing anchors in the posterosuperior glenoid through an anterolateral portal. Use of the posterolateral portal results in a much lower incidence of glenoid perforation for anchors placed in the posterosuperior glenoid, but there is a higher risk of glenoid perforation for an anchor placed in the anterosuperior glenoid from the posterolateral portal. CLINICAL RELEVANCE: There is a higher risk of injury to the suprascapular nerve when suture anchors are placed in the posterosuperior glenoid through an anterolateral portal compared with a posterolateral portal for SLAP repair.

Investigation of multiligamentous knee injury patterns with associated injuries presenting at a level I trauma center.

OBJECTIVES: To characterize multiligamentous knee injury patterns and describe associated morbidities. DESIGN: Retrospective. SETTING: Level I trauma center. PATIENTS: One hundred two patients (106 knees) with multiligamentous knee injuries and/or dislocations from 2000 through 2008. Subgroup of 82 knees with appropriate magnetic resonance images available assessed for ligamentous injury patterns. INTERVENTION: Data obtained from medical records for 106 knees. MAIN OUTCOME MEASUREMENTS: Presence of arterial injuries, nerve injuries, associated fracture patterns, and whole-body morbidities. RESULTS: The most common (43%) injury pattern was a combined disruption of the anterior cruciate ligament, posterior cruciate ligament, and posterolateral corner. Twenty-five percent of knees had associated ipsilateral tibial plateau fractures, and 19% had associated ipsilateral femoral fractures. Peroneal nerve injury occurred in 25% of knees, arterial injury in 21%, and compartment syndrome in 16%. An intra-abdominal injury was present in 13% of patients, a severe closed head injury in 10%, and a symptomatic pulmonary embolism in 5%. CONCLUSIONS: Nearly half the multiligamentous knee injuries involved the anterior cruciate ligament, posterior cruciate ligament, and posterolateral corner; one-fourth had associated ipsilateral tibial plateau fractures. The incidence of peroneal nerve injury (25%) was higher than previously reported (20%), whereas the incidence of arterial injury (21%) was comparable to previous reports (19%). Posterolateral corner injuries were more prevalent than previously reported and were highly associated with peroneal nerve injury. We found a substantial incidence of associated morbidities of the whole body. Multiligamentous knee injuries are a marker of concomitant trauma and should be closely evaluated at presentation and during the hospital course to allow for early intervention for life- or limb-threatening comorbidities.

Arthroscopic suture anchor capsulorrhaphy versus labral-based suture capsulorrhaphy in a cadaveric model.

PURPOSE: The purpose of this study was to establish whether suture anchor capsulorrhaphy (SAC) is biomechanically superior to suture capsulorrhaphy (SC) in the management of recurrent anterior shoulder instability without a labral avulsion. METHODS: Twelve matched pairs of shoulders were randomized to either SC or SAC. Specimens were mounted in 60° of abduction and 90° of external rotation. Testing was conducted on an MTS servohydraulic load testing device (MTS, Eden Prairie, MN). A compressive load of 22 N was applied, followed by a 2-N anterior and posterior force to establish a 0 point. Translation with 10-N anterior and posterior loads was recorded for baseline laxity measurement. Arthroscopic capsulorrhaphy was performed with either 3 solitary sutures or 3 suture anchors. Specimens were remounted and returned to the 0 point. Translation was measured with 10-N anterior and posterior loads to determine reduction in translation. Specimens were then loaded to failure to the 0 point at a rate of 0.1 mm/s. RESULTS: Load to failure was significantly greater (P = .02) in the SC group (13.6 ± 1.0 N) versus the SAC group (20.5 ± 2.8 N). No differences were found between SC (2.7 ± 0.7 mm) and SAC (2.3 ± 0.6 mm) when we compared reduction of anterior translation with a 10-N load. The percent reduction of anterior displacement with a 10-N load was similar for the SC (49.9%) and SAC (49.6%) groups. The dominant mode of failure in the study was suture pull-through of the capsular tissue. CONCLUSIONS: Our study indicates that labral-based SC and SAC similarly reduce anterior glenohumeral translation at low loading conditions. Load-to-failure studies indicate that SAC exhibits significantly greater resistance to translation at higher loading conditions. Our study suggests that the use of a suture anchor when one is performing a capsulorrhaphy may provide biomechanical advantage at high loading conditions. CLINICAL RELEVANCE: Our study suggests that when one is performing capsulorrhaphy, the use of a suture anchor may provide biomechanical advantages at high loading conditions.

Chondrocyte survival and material properties of hypothermically stored cartilage: an evaluation of tissue used for osteochondral allograft transplantation.

BACKGROUND: There is little information available on the material properties of hypothermically stored allograft specimens used to repair osteochondral defects. PURPOSE: To analyze the effect of hypothermic storage on the material properties of fresh knee specimens over a 60-day interval. STUDY DESIGN: Controlled laboratory study. METHODS: Twelve sheep knee condyles were isolated. The femoral and tibial condyles and the patella were stored in a nutritive medium containing Dulbecco's Modified Eagle's Medium for 1, 8, 15, 29, 45, or 60 days. Total chondrocyte density, chondrocyte viability, matrix proteoglycan content, matrix water content, and matrix dynamic modulus of elasticity were determined. RESULTS: Mean chondrocyte viability decreased significantly over the storage interval: 100% (day 1), 98.2% (day 8), *80.2% (day 15), *80.6% (day 29), *64.6% (day 45), and *51.6% (day 60) (* P < 0.05). Qualitative analysis demonstrated a preponderance of nonviable chondrocytes in the superficial cartilage layer. Significant decreases in matrix proteoglycan were observed in day 15 through day 60 specimens (P < 0.05). The matrix dynamic modulus significantly decreased from day 1 through day 60 (P < 0.05). CONCLUSION: The material properties of hypothermically stored knee condyles progressively decline over 60 days. CLINICAL RELEVANCE: This observed decline may have significant ramifications on long-term graft survival following stored-allograft implantation.