Distal avulsion of reconstituted hamstring tendons.

PURPOSE: Hamstring tendon autograft (semitendinosus and gracilis) is the most commonly used graft in anterior cruciate ligament (ACL) reconstruction. Distal hamstring tendons avulsion is a rare condition, and this paper describes a previously unreported injury, local management of this rare injury pattern, and the existing literature regarding treatment options. METHODS: Two cases are presented of distal hamstring avulsion from the tibia of reconstituted tendons, together with additional 12 cases of distal hamstrings tendon avulsion. Functional outcomes following treatment of this injury are presented, together with a literature review of management options. RESULTS: Early surgical reattachment using suture anchor fixation was performed and excellent results were achieved in 93% of cases (13 out of 14 patients). Patient-reported outcome measures demonstrated a median Marx score 14.5 (IQR 4) and median SHORE score 34.5 (IQR 4). The mean time to surgery was 22 days (range 5-60), with mean time to return to sport at pre-injury level 5.5 months (range 2.5-12). CONCLUSIONS: Distal hamstring tendon avulsion is a rare condition, with no consensus regarding optimal management options. Acute surgical repair leads to excellent results, with a return to pre-injury level of sporting activity. LEVEL OF EVIDENCE: IV.

Medial meniscal cyst as a cause of painful erosion of the tibial plateau.

Medial cysts are rarely encountered as a cause of bone erosion. It is thought meniscal cysts are present in up to 22 % of meniscal tear operations. MRI is the gold standard for visualisation of meniscal cysts. Decompression is often guided by careful study of the pre-operative MRI scans in multiple planes. This is the first case report demonstrating erosion of the medial tibial plateau due to an incarcerated meniscal cyst highlighting the potential for bone damage if left untreated. Level of evidence IV.

Outcomes following adolescent athlete proximal hamstring apophyseal avulsion bone fragment excision and direct tendon-ischial tuberosity reattachment.

Apophyseal proximal hamstring bone avulsion is uncommon, occurring in adolescents following sudden forceful contraction of the musculotendinous unit. It can be severely disabling, preventing return to sport. This study assessed outcome following avulsed bone excision and direct hamstring tendon-ischial tuberosity reattachment using bone anchors. Validated hamstring-specific Sydney hamstring orthopaedic research evaluation PROMs were prospectively collected from consecutively treated athletes (7 elite and 11 recreational) by a single surgeon over 13 years. Outcomes at 1-year and final follow-up for primary acute surgery at less than 3 months after injury (group 1), primary chronic surgery at more than 3 months after established nonunion (group 2) and revision following failed screw fixation (group 3) were analyzed with sport participation and level at 1 year. Sixteen primary and two revision procedures were analyzed. Mean injury age was 14.6 years (SD, 1.8). Combined primary mean injury scores improved from 11.89 (SD, 7.32) to 33.31 (SD, 2.30) and showed mean 1 year and final follow-up scores within 0.3-6.1% of preinjury values. Pronounced improvement occurred from injured scores for groups 1 versus 2, respectively at 1 year by 247.7% versus 59.0% and at final follow-up by 251.0% versus 64.1%, for groups 1 versus 2, respectively. Final outcome scores of group 3 were high. All cases returned to preinjury sport level by 1 year and indicated satisfaction to repeat treatment. No significant complications occurred. As the largest series to assess outcomes following this surgical technique, success is highlighted by high score improvements close to preinjury values and return to preinjury sport level.

Acute presentation of a proximal fibular stress fracture after a total knee arthroplasty.

A 67-year-old woman underwent a routine and uneventful elective total knee arthroplasty for osteoarthritis at our centre. No intraoperative nor immediate postoperative complications were noted clinically nor radiologically. At 5 weeks postoperative, she began to notice some new discomfort in her upper calf area, with no preceding history of trauma. A Doppler ultrasound scan ruled out a deep vein thrombus. Only on further re-imaging of her knee with X-rays and CT was there shown to be a fibular fracture of the proximal third with evidence of callus formation. The pain arising from her stress fracture delayed her rehabilitation slightly, going on to require a successful manipulation under anaesthetic (0°-95°). She went on to have excellent function in her knee and the pain from the stress fracture had settled by 5 months.

Hamstring injuries: anatomy, imaging, and intervention.

Injury to the hamstring muscle complex (HMC) is extremely common in the athletic community. Anatomical and functional aspects of the HMC predispose it to injury, including the fact that the muscles cross two joints and undergo eccentric contraction during the gait cycle. Injury most commonly occurs at the muscle tendon junction but may occur anywhere between the origin and insertion. Complete hamstring avulsions require early surgical repair. The principal indication for imaging is in a triage role to rule out or confirm proximal hamstring avulsion. Acute onset and chronic posterior thigh and buttock pain may relate to pathology at the hamstring origin or muscle tendon junction that can be readily defined on magnetic resonance imaging or, less frequently, ultrasound. Some cases of buttock and thigh pain may relate to spinal pathology. In the elite athlete there is an increasing emphasis on optimizing the rehabilitation process after hamstring injury, to minimize the absence from sports and improve the final outcome. Imaging has a role in confirming the site of injury and characterizing its extent, providing some prognostic information and helping plan treatment. There is increasing interest in the use of growth factors to accelerate healing after muscle and tendon injury. Animal studies have demonstrated clear benefits in terms of accelerated healing. There are various methods of delivery of the growth factors, all involving the release of growth factors from platelets. These include plasma rich in platelets and autologous blood. Clinical studies in humans are very limited at this stage but are promising. At present the World Anti-Doping Authority bans the intramuscular administration of these agents. Other percutaneous injection therapies include the use of Actovegin and Traumeel S and antifibrotic agents.

Validation of the Sydney Hamstring Origin Rupture Evaluation (SHORE).

AIMS: To validate the Sydney Hamstring Origin Rupture Evaluation (SHORE), a hamstring-specific clinical assessment tool to evaluate patient outcomes following surgical treatment. METHODS: A prospective study of 70 unilateral hamstring surgical repairs, with a mean age of 47.3 years (15 to 73). Patients completed the SHORE preoperatively and at six months post-surgery, and then completed both the SHORE and Perth Hamstring Assessment Tool (PHAT) at three years post-surgery. The SHORE questionnaire was validated through the evaluation of its psychometric properties, including; internal consistency, reproducibility, reliability, sensitivity to change, and ceiling effect. Construct validity was assessed using Pearson's correlation analysis to examine the strength of association between the SHORE and the PHAT. RESULTS: The SHORE demonstrated an excellent completion rate (100%), high internal consistency (Cronbach's alpha 0.78), and good reproducibility (intraclass correlation coefficient (ICC) 0.82). The SHORE had a high correlation with the validated PHAT score. It was more sensitive in detecting clinical change compared to the PHAT. A ceiling effect was not present in the SHORE at six months; however, a ceiling effect was identified in both scores at three years post-surgery. CONCLUSION: This study has validated the SHORE patient reported outcome measure (PROM) as a short, practical, reliable, valid, and responsive tool that can be used to assess symptom and function following hamstring injury and surgical repair. Cite this article: Bone Joint J 2020;102-B(3):388-393.

The Natural History of Biointerference Screw Cyst and New Bone Formation in Anterior Cruciate Ligament Reconstruction: 16-Year Follow-up.

BACKGROUND: A variety of fixation devices are available for anterior cruciate ligament reconstruction (ACLR). Bioabsorbable screws allow imaging postoperatively without image artefact, as with magnetic resonance imaging (MRI). There is also the perceived benefit of screw resorption and subsequent host tunnel bone ingrowth. PURPOSE/HYPOTHESIS: The purpose of this study was to document the natural history of poly L-lactic acid (PLLA) bioabsorbable interference screws. Manufacturers claimed that screws would be resorbed and replaced by new bone within 2 years. The hypothesis was that these screws take considerably longer to achieve this claim. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Ten consecutive patients undergoing routine ACLR with a PLLA bioabsorbable RCI screw (Arthrex) and a standard 4-strand hamstring graft technique were assessed via MRI and telephone questionnaire at 1, 2, 4, 7, 10, and 16 years postoperatively. RESULTS: At 4-year follow-up, no resorption of the screw or bone formation had occurred. At 7-year follow-up, absorption of 7 screws was complete, cyst formation had occurred in 3 patients, and 5 patients had new bone formation. At 10-year follow-up, all screws were reabsorbed, cyst formation was evident in only 2 cases, and 7 patients had evidence of new bone formation. At 16-year follow-up, cyst formation was only present in 1 patient, and all patients had evidence of new bone formation. All patients had an intact anterior cruciate ligament and had returned to preinjury sporting activity. CONCLUSION: PLLA bioabsorbable screws take longer to resorb than previously thought by the manufacturers (ie, 2 years). New bone formation is evident in 100% of patients by 16 years. Cyst formation does not occur in all patients with a bioabsorbable screw implant. In the 3 patients demonstrating the presence of a cyst, no associated adverse effects were found with regard to anterior cruciate ligament graft survival or instability.

The natural history of a bioabsorbable interference screw used for anterior cruciate ligament reconstruction with a 4-strand hamstring technique.

PURPOSE: The purpose of this study was to assess radiologically the rate of absorption of the Arthrex poly L-lactide bioabsorbable interference screw (Arthrex, Naples, FL) used in anterior cruciate ligament reconstruction with a 4-strand hamstring technique. TYPE OF STUDY: Case series. METHODS: Eight sequential patients undergoing anterior cruciate ligament reconstruction with a 4-strand hamstring technique were assessed with magnetic resonance imaging (MRI) scans at 1, 2, and 4 years postoperatively. RESULTS: There was no radiologic evidence of absorption of the screw on any of the scans. The MRI appearance remained essentially unchanged from 1 to 4 years with the exception of the presence of a small cyst in the tibial tunnel of one of the patients. No edema was seen associated with the tibial tunnel in any of our patients. CONCLUSIONS: There are several quoted theoretical advantages to using bioabsorbable screws. The rate of absorption is dependent on material, weight, and degree of crystallization. In our series using an amorphous low crystallization poly L-lactide screw, there was no evidence of any progression to absorption 4 years after implantation. This may be because all series quoted to date look at absorption using a bone-patellar tendon-bone graft. LEVEL OF EVIDENCE: Level IV.

Bio-interference screw cyst formation in anterior cruciate ligament reconstruction--10-year follow up.

PURPOSE: This study used serial MRI to assess the absorption of a poly l-lactide Bioabsorbable interference screw used in the anterior cruciate ligament reconstruction with a 4-strand hamstring technique. METHODS: A consecutive series of ten patients undergoing anterior cruciate ligament reconstruction a 4-strand hamstring technique were assessed with magnetic resonance imaging (MRI) scans at 1, 2, 4, 7 and 10 years postoperatively. RESULTS: No resorption had occurred after 4 years in any of the patients. By 7 years screw absorption was complete in seven patients and had progressed in three. New cyst formation occurred in 3 patients between 5 and 7 years. Half the patients displayed small fluid collections within the tibial tunnels. At 10 years all screws were fully absorbed; however cyst formation was common, including the development of a new cyst in the period between 7 and 10 years in one patient. None of the patients had instability, persistent effusions, or clinically detectable adverse reactions to the screws. CONCLUSIONS: This study has shown that poly l-lactide bioabsorbable screws take longer to resorb than initial in vitro data suggested. It is unclear whether ganglion formation within the tibial tunnel is related to screw resorption or the hamstring graft. The theoretical advantages of bioabsorbable screws must be weighed against these findings.

Isolated avulsion of the vastus lateralis tendon insertion in a weightlifter: a case report.

INTRODUCTION: We report a case of isolated, unilateral avulsion of the vastus lateralis tendon from its insertion at the patella. This was diagnosed by magnetic resonance imaging, and underwent successful surgical repair. CASE PRESENTATION: A healthy 32-year-old national level power lifter presented with an isolated avulsion of the vastus lateralis tendon. After a failed course of conservative therapy he underwent surgical repair and a graded physical therapy programme. One year later he returned to full training with no evidence of re-rupture. CONCLUSION: This is the first reported case of an isolated vastus lateralis avulsion. Our experience suggests that magnetic resonance imaging is invaluable in the diagnosis of this condition and that surgical repair provides a good outcome in high demand patients.

Avulsion of the proximal hamstring origin. Surgical technique.

BACKGROUND: The torn hamstring is a common athletic injury. The purpose of the present study was to review the clinical presentation of this injury, the diagnostic imaging findings, the surgical technique of reattachment, and the likely clinical outcome of surgery for the treatment of avulsion of the proximal hamstring origin. METHODS: Seventy-two consecutive reconstructions in seventy-one patients with avulsion of the proximal hamstring origin were performed at a single center. The mean age at the time of the operation was 40.2 years. The mean duration of follow-up was twenty-four months, and all patients with a minimum duration of follow-up of six months were included. There were no exclusions. Patients were independently reviewed, and the mean postoperative isotonic hamstring strength was compared with that on the uninjured side. RESULTS: Waterskiing was the most frequent cause of injury (twenty-one cases). The mean time between the injury and the operation was twelve months. The most common pathological finding was a complete avulsion of the proximal hamstring origin (sixty-three cases; 87.5%), with a mean retraction of 7 cm (range, 0 to 20 cm). The mean postoperative isotonic hamstring strength measured 84% (range, 43% to 122%) and the mean postoperative hamstring endurance measured 89% (range, 26% to 161%) when compared with the values on the contralateral side. CONCLUSIONS: It is important to distinguish proximal hamstring origin avulsions (for which we recommend early surgical repair) from the majority of hamstring muscle injuries (which respond well to nonoperative treatment). The present study suggests that, in cases of complete avulsion with hamstring retraction, a delay in surgical repair renders the repair more technically challenging, may increase the likelihood of sciatic nerve involvement, increases the need for postoperative bracing, and reduces postoperative outcome in terms of hamstring strength and endurance. Once the nature of the injury has been established, the surgical treatment of hamstring origin avulsions has predictable and satisfactory results.

Avulsion of the proximal hamstring origin.

BACKGROUND: The torn hamstring is a common athletic injury. The purpose of the present study was to review the clinical presentation of this injury, the diagnostic imaging findings, the surgical technique of reattachment, and the likely clinical outcome of surgery for the treatment of avulsion of the proximal hamstring origin. METHODS: Seventy-two consecutive reconstructions in seventy-one patients with avulsion of the proximal hamstring origin were performed at a single center. The mean age at the time of the operation was 40.2 years. The mean duration of follow-up was twenty-four months, and all patients with a minimum duration of follow-up of six months were included. There were no exclusions. Patients were independently reviewed, and the mean postoperative isotonic hamstring strength was compared with that on the uninjured side. RESULTS: Waterskiing was the most frequent cause of injury (twenty-one cases). The mean time between the injury and the operation was twelve months. The most common pathological finding was a complete avulsion of the proximal hamstring origin (sixty-three cases; 87.5%), with a mean retraction of 7 cm (range, 0 to 20 cm). The mean postoperative isotonic hamstring strength measured 84% (range, 43% to 122%) and the mean postoperative hamstring endurance measured 89% (range, 26% to 161%) when compared with the values on the contralateral side. CONCLUSIONS: It is important to distinguish proximal hamstring origin avulsions (for which we recommend early surgical repair) from the majority of hamstring muscle injuries (which respond well to nonoperative treatment). The present study suggests that, in cases of complete avulsion with hamstring retraction, a delay in surgical repair renders the repair more technically challenging, may increase the likelihood of sciatic nerve involvement, increases the need for postoperative bracing, and reduces postoperative outcome in terms of hamstring strength and endurance. Once the nature of the injury has been established, the surgical treatment of hamstring origin avulsions has predictable and satisfactory results.