The LockDown device (previously called Surgilig) is a braided polyester mesh which is mostly used to reconstruct the dislocated acromioclavicular joint. More than 11 000 have been implanted worldwide. Little is known about the tissue reaction to the device nor to its wear products when implanted in an extra-articular site in humans. This is of importance as an adverse immunological reaction could result in osteolysis or damage to the local tissues, thereby affecting the longevity of the implant.

We analysed the histology of five LockDown implants retrieved from five patients over the last seven years by one of the senior authors. Routine analysis was carried out in all five cases and immunohistochemistry in one.

The LockDown device acts as a scaffold for connective tissue which forms an investing fibrous pseudoligament. The immunological response at the histological level seems favourable with a limited histiocytic and giant cell response to micron-sized wear particles. The connective tissue envelope around the implant is less organised than a native ligament.

Cite this article: Bone Joint J 2015;97-B:83–8.

Management of highly displaced acromioclavicular joint (ACJ) injuries remain contentious. It is unclear if delayed versus acute reconstruction has an increased risk of fixation failure and complications. The primary aim of this was to compare complications of early versus delayed reconstruction. The secondary aim was to determine modes of failure of ACJ reconstruction requiring revision surgery. A retrospective study was performed of all patients who underwent operative reconstruction of ACJ injuries over a 10-year period (Rockwood III-V). Reconstruction was classed as early (<12 weeks from injury) or delayed (≥12 weeks). Patient demographics, fixation method and post-operative complications were noted, with one-year follow-up a minimum requirement for inclusion. Fixation failure was defined as loss of reduction requiring revision surgery. 104 patients were analysed (n=60 early and n=44 delayed). Mean age was 42.0 (SD 11.2, 17–70 years), 84.6% male and 16/104 were smokers. No difference was observed between fixation failure (p=0.39) or deep infection (p=0.13) with regards to acute versus delayed reconstruction. No patient demographic or timing of surgery was predictive of fixation failure on regression modelling. Overall, eleven patients underwent revision surgery for loss of reduction and implant failure (n=5 suture fatigue, n=2 endo-button escape, n=2 coracoid stress fracture and n=2 deep infection). This study suggests that delayed ACJ reconstruction does not have a higher incidence of fixation failure or major complications compared to acute reconstruction. For those patients with ongoing pain and instability following a trial of non-operative treatment, delayed reconstruction would appear to be a safe treatment approach

Osteolysis has been reported following ACJ reconstruction with a synthetic graft. We present the first study into its prevalence and pattern, and its effect on patient outcome. Patients who underwent treatment of an unstable ACJ injury using the Surgilig/LockDown implant were identified via our database. Patients were invited to attend a dedicated outpatient clinic for clinical examination, radiographic evaluation, and completion of outcome scoring. Patients who were unable to attend were contacted by telephone. 49 patients were identified. We assessed 21 clinically at a mean of 7 years post-procedure (range 3–11 years). All had radiographic evidence of distal clavicle and coracoid osteolysis. We did not observe progression of osteolysis from the final post-operative radiographs. A further 13 were contacted by phone. The mean Oxford Shoulder Score was 43 (range 31–48) and mean DASH score was 8.5 (range 3–71). The average Patient Global Impression of Change score was 6 (range 2–7). Six patients underwent removal of a prominent screw at a mean of 2 years after surgery; the pattern of osteolysis was no different in this group. All patients had comparable abduction, forward flexion and internal rotation to their uninjured shoulder. We did not observe any relationship between patient demographics, position of implant or etiology and the pattern of osteolysis. Osteolysis of the distal clavicle and/or coracoid is always seen following synthetic reconstruction of the ACJ using this implant, but is non-progressive. Range of shoulder movement is largely unaffected and patient outcomes remain high

Aims

To compare radiographic failure and re-operation rates of anatomical coracoclavicular (CC) ligament reconstructional techniques with non-anatomical techniques after chronic high grade acromioclavicular (AC) joint injuries.

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The aim of this review is to address controversies in the management of dislocations of the acromioclavicular joint. Current evidence suggests that operative rather than non-operative treatment of Rockwood grade III dislocations results in better cosmetic and radiological results, similar functional outcomes and longer time off work. Early surgery results in better functional and radiological outcomes with a reduced risk of infection and loss of reduction compared with delayed surgery.

Surgical options include acromioclavicular fixation, coracoclavicular fixation and coracoclavicular ligament reconstruction. Although non-controlled studies report promising results for arthroscopic coracoclavicular fixation, there are no comparative studies with open techniques to draw conclusions about the best surgical approach. Non-rigid coracoclavicular fixation with tendon graft or synthetic materials, or rigid acromioclavicular fixation with a hook plate, is preferable to fixation with coracoclavicular screws owing to significant risks of loosening and breakage.

The evidence, although limited, also suggests that anatomical ligament reconstruction with autograft or certain synthetic grafts may have better outcomes than non-anatomical transfer of the coracoacromial ligament. It has been suggested that this is due to better restoration horizontal and vertical stability of the joint.

Despite the large number of recently published studies, there remains a lack of high-quality evidence, making it difficult to draw firm conclusions regarding these controversial issues.

Cite this article: Bone Joint J 2013;95-B:1595–1602.