There is currently no commercially available and clinically successful treatment for scapholunate interosseous ligament rupture, the latter leading to the development of hand-wrist osteoarthritis. We have created a novel biodegradable implant which fixed the dissociated scaphoid and lunate bones and encourages regeneration of the ruptured native ligament. To determine if scaphoid and lunate kinematics in cadaveric specimens were maintained during robotic manipulation, when comparing the native wrist with intact ligament and when the implant was installed.

Ten cadaveric experiments were performed with identical conditions, except for implant geometry that was personalised to the anatomy of each cadaveric specimen. Each cadaveric arm was mounted upright in a six degrees of freedom robot using k-wires drilled through the radius, ulna, and metacarpals. Infrared markers were attached to scaphoid, lunate, radius, and 3rd metacarpal. Cadaveric specimens were robotically manipulated through flexion-extension and ulnar-radial deviation by ±40° and ±30°, respectively.

The cadaveric scaphoid and lunate kinematics were examined with 1) intact native ligament, 2) severed ligament, 3) and installed implant.

Digital wrist models were generated from computed tomography scans and included implant geometry, orientation, and location. Motion data were filtered and aligned relative to neutral wrist in the digital models of each specimen using anatomical landmarks. Implant insertion points in the scaphoid and lunate over time were then calculated using digital models, marker data, and inverse kinematics. Root mean squared distance was compared between severed and implant configurations, relative to intact.

Preliminary data from five cadaveric specimens indicate that the implant reduced distance between scaphoid and lunate compared to severed configuration for all but three trials.

Preliminary results indicate our novel implant reduced scapho-lunate gap caused by ligament transection. Future analysis will reveal if the implant can achieve wrist kinematics similar to the native intact wrist.

Chauffeur fractures or isolated radial styloid fractures (IRSF) are known to be associated with scapholunate ligament (SL) injuries. Diagnosis without arthroscopic confirmation is difficult in acute fractures. Acute management of this injury with early repair may prevent the need for more complex reconstructive procedures for chronic injuries. We investigated if all IRSF should be assessed arthroscopically for concomitant SL injuries.

We performed a prospective cohort study on patients above the age of 16, presenting to the Gold Coast University Hospital with an IRSF, over 2 years. Plain radiographs and computerized tomography (CT) scans were performed. All patients had a diagnostic wrist arthroscopy performed in addition to an internal fixation of the IRSF. Patients were followed up for at least 3 months post operatively. SL repair was performed for all Geissler Grade 3/4 injuries.

10 consecutive patients were included in the study. There was no radiographic evidence of SL injuries in all patients. SL injuries were identified arthroscopically in 60% of patients and one third of these required surgical stabilisation. There were no post operative complications associated with wrist arthroscopy.

We found that SL injuries occurred in 60% of IRSF and 20% of patients require surgical stabilisation. This finding is in line with the literature where SL injuries are reported in up to 40-80% of patients. Radiographic investigations were not reliable in predicting possible SL injuries in IRSF. However, no SL injuries were identified in undisplaced IRSF. In addition to identifying SL injuries, arthroscopy also aids in assisting and confirming the reduction of these intra-articular fractures.

In conclusion, we should have a high index of suspicion of SL injury in IRSF. Arthroscopic assisted fixation should be considered in all displaced IRSF. This is a safe additional procedure which may prevent missed SL injuries and their potential sequelae.

The primary aim of this study was to identify the rate of osteoarthritis in scaphoid fracture non-union. We also aimed to investigate whether the incidence of osteoarthritis correlates with the duration of non-union(interval), and to identify the variables that influence the outcome. We retrospectively reviewed 273 scaphoid fracture non-union presented between 2007 and 2016. Data included patient demographics, interval, fracture morphology, grade of osteoarthritis (Kellgren-Lawrence) and scaphoid non-union advanced collapse (SNAC), and overall health-related quality of life. Patients were divided into two groups (SNAC and Non-SNAC). Group differences were analysed using Mann-Whitney U test and association with Pearson's correlations. A two-sided p-value of <0.05 was considered significant.

The scaphoid fracture non-union were confirmed on CT scans (n=243) and plain radiographs (n=35). The subjects were 32 females and 260 males with the mean age of 33.8 years (SD, 13.2). The average interval was 3.1 years (range, 0–45 years). Osteoarthritis occurred in 58% (n=161) of non-unions, and 42% (n=117) had no osteoarthritis. In overall, 38.5% (n=107) had SNAC-1, 9% (n=25) with SNAC-2, and 10.4% (n=29) presented with SNAC-3. The mean interval in the non-SNAC group was 1.2 years, and in SNAC 1,2, and 3 were 2.6, 6.8, and 11.1 years, respectively. The average summary index in SNAC and non- SNAC groups was 0.803 and 0.819, respectively. Our results also showed a significant correlation between advanced osteoarthritis and proximal fracture non-unions(P<0.05).

We concluded that there is no clear correlation between the interval and the progression of osteoarthritis. SNAC was more likely to occur in fractures aged 2 years or older.

Introduction

Management of painful scarring of a nerve after surgery or trauma is challenging. Wrapping with a vein or adhesion barriers such as silicone have been reported with some success. This is a retrospective review of application of a xenograft collagen wrap around a peripheral nerve following neurolysis. There is no report in English literature of use of a collagen wrap for this purpose.

The ‘Pi’ plate is an anatomical titanium plate recently introduced for the internal fixation of comminuted intra-articular distal radius fractures. We report our experience with this implant in a prospective series of twelve patients with an average age of thirty six years (range, 26–52 years).

A dorsal approach with release of the EPL tendon and extra-compartmental exposure of the radius between the second and fourth extensor compartments was employed in all cases. Iliac bone graft and a styloid K-wire were used to augment the plate fixation. Post-operatively, active mobilisation was started after wound healing. Wrist motion and grip strength measurements were made at six weeks, three months and six months by the therapist. At six months, patients recovered an average of 85% of range of movement compared with the opposite wrist, except for palmar flexion (65%). No loss of reduction was observed on follow-up radiographs. Complications were compartment syndrome, intraoperative EPL rupture and two cases of extensor tendonitis requiring implant removal.

The ‘Pi’ plate affords rigid fixation of distal radius fractures permitting early rehabilitation. It is however a demanding technique that is not without complications.