Loss of flexor pollicis longus function after plating of the radius. Report of six cases

Locked Wire Fixator for a Distal Radius Fracture With Malunion: A Case Report

Surgical treatment for a distal radius fracture using a volar locking plate is difficult if the distal radius malunion remains. Therefore, a different surgical method from volar locking plate fixation should be required. We report the case of an 83-year-old woman with a left dorsal displaced distal radius fracture. However, the deformity of the volar cortex of the radius was recognized because of a previous distal radius fracture. Therefore, osteosynthesis with a locked wire fixator was performed. At 12 months after surgery, the patient has returned to daily activities without difficulty. A locked wire fixator can be useful for treating a distal radius fracture with malunion of the volar cortex of the distal radius.

Marinacci Anastomosis: A Case Report

Marinacci anastomosis or the reverse Martin-Gruber anastomosis is a rare anomalous intercommunication from the ulnar nerve to the median nerve in the forearm. A young lady was involved in a road traffic accident that resulted in the fracture of both forearm bones for which she was treated surgically. A nerve conduction study was performed later on, which incidentally demonstrated findings of this communication. Knowledge of this anastomosis can help prevent misdiagnosis of clinical findings and misinterpretation of electrophysiological studies and help mitigate iatrogenic injury during surgical procedures.

Anterior Interosseous Nerve Palsy After Shoulder Arthroscopy Treated With Surgical Decompression: A Case Series and Systematic Review of the Literature

Background: Anterior interosseous nerve (AIN) palsy is a very uncommon cause of upper extremity pain and weakness that comprises less than 1% of all upper extremity nerve palsies. Rarely reported but also mentioned in the literature is AIN palsy after shoulder arthroscopy. Methods: A systematic review of the literature to date using PubMed was conducted to identify patients who suffered AIN palsy after shoulder arthroscopy procedures. Articles included met the following criteria: (1) published in English; (2) primary presentation of the data; (3) patients had undergone shoulder arthroscopy before developing symptoms of AIN palsy; and (4) diagnosis was confirmed with clinical symptoms of AIN palsy. Measured outcomes included patient demographics, specific shoulder procedure, anesthesia procedure, intra-operative patient positioning, intra-operative compressive dressing, intra-operative traction, surgical versus conservative treatment, abnormal findings during decompression procedure, proposed mechanism of injury, and follow-up. Results: The search yielded 6 articles, of which 4 (13 cases) met inclusion criteria. An additional 2 cases were included in this report totaling 15 cases. The average patient age was 49 years (range: 31-64) with 73% males. At average follow-up of 24 months, 67% of patients experienced complete resolution of symptoms-more than half of which underwent surgical decompression. Patients who failed to progress experienced weakness of the flexor digitorum profundus and flexor pollicis longus muscles. Conclusions: Proposed injury mechanisms for AIN palsy after shoulder arthroscopy range from mechanical trauma, compressive hematoma, and direct anesthetic neurotoxicity. Management should be directed by clinical symptoms, imaging, and patient factors with majority of patients expected to have excellent clinical outcomes.

Persistent anterior interosseous nerve palsy following forearm crutch use

A 43-year-old man presented with weakness of the interphalageal joint of his right thumb following the use of forearm crutches. On examination he was unable to oppose his thumb and index finger to form the 'ok' sign. Nerve conduction showed anterior interosseous nerve (AIN) damage along its path to the flexor pollicis longus. The patient was managed conservatively with little clinical improvement seen at 4 months. AIN palsies are very rare and account for <1% of all upper limb lesions. Although AIN palsies resulting from other causes such as surgery and blunt trauma are more common, we report the second case of AIN palsy following crutch use, and the first case in which clinical identification was confirmed using electrodiagnosis. Usual clinical practice recommends a prolonged period of conservative management with surgical management withheld for a minimum of 12 months. Correct crutch fitting and early identification of signs of associated injuries are of paramount importance.

Flexor pollicis longus dysfunction after volar plate fixation of distal radius fractures

PURPOSE

To evaluate the natural history and etiology of decreased thumb interphalangeal (IP) joint flexion after volar plate fixation of distal radius fractures.

METHODS

A total of 46 patients who underwent volar plating of 48 distal radius fractures by a single surgeon were retrospectively studied. Of those patients, 24 (24 wrists) exhibited loss of thumb IP joint flexion (group 1) and 22 (24 wrists) retained thumb IP joint flexion (group 2) with attempted thumb opposition to the small finger after surgery. All patients were seen at regular intervals until IP joint flexion returned and fracture healing was confirmed radiographically. Patient demographics, fracture patterns, surgical variables, and final radiographs were compared between groups. Twenty patients in group 1 were seen after a mean of 6.5 months (range, 5-12 mo) for specific outcome measurements. Eight cadaveric specimens were used to replicate the flexor carpi radialis approach to the distal radius and evaluate flexor pollicis longus tendon excursion.

RESULTS

There were no significant differences in fracture pattern, patient age or sex, injured extremity dominance, time to surgery, incision length, plate composition, plate length, tourniquet time, or final wrist radiographs between groups. In group 1, active thumb IP joint flexion returned on average 52 days (range, 19-143 d) postoperatively. At final evaluation in this group, mean IP joint flexion was 11° less than the contralateral thumb IP joint; however, patient-determined outcomes were favorable in most cases. In the cadaveric specimens, excursion of the flexor pollicis longus tendon decreased with sequential soft tissue dissection and retraction.

CONCLUSIONS

Loss of thumb IP joint flexion after volar plating of distal radius fractures was common, and motion returned to near normal in most cases within 2 months. Partial stripping of the flexor pollicis longus muscle from investing fascia and bone and retraction of soft tissues are likely etiological factors.

Anterior interosseous nerve syndrome: retrospective analysis of 14 patients

INTRODUCTION

The anterior interosseous nerve (AIN) is a only motor nerve innervating the deep muscles of the forearm. Its compression is rare. We present a retrospective analysis of 14 patients with an AIN syndrome with a variety of clinical manifestations who underwent operative and conservative treatment.

PATIENTS AND METHODS

Fourteen patients (six female, eight male, mean age 48 ± 9 years) were included. In six patients, the right limb was affected, and in eight patients the left limb. Conservative treatment was started for every patient. If no signs of recovery appeared within 3 months, operative exploration was performed. Final assessment was performed between 2 and 9 years after the onset of paralysis (mean duration of follow-up 46 ± 11 months). Patients were examined clinically for return of power, range of motion, pinch and grip strengths. Also the disability of the arm, shoulder, and hand (DASH) score was calculated.

RESULTS

Seven of our 14 patients had incomplete AIN palsy with isolated total loss of function of flexor pollicis longus (FPL), five of FPL and flexor digitorum profundus (FDP)1 simultaneously, and two of FDP1. Weakness of FDP2 could be seen in four patients. Pronator teres was paralysed in two patients. Pain in the forearm was present in nine patients. Four patients had predisposing factors. Eight patients treated conservatively exhibited spontaneous recovery from their paralysis during 3-12 months after the onset. In six patients, the AIN was explored 12 weeks after the initial symptoms and released from compressing structures. Thirteen patients showed good limb function. In one patient with poor result a tendon transfer was necessary. The DASH score of patients treated conservatively and operatively presented no significant difference.

CONCLUSION

AIN syndrome can have different clinical manifestations. If no signs of spontaneous recovery appear within 12 weeks, operative treatment should be performed.

Flexor pollicis longus tendon ruptures after palmar plate fixation of fractures of the distal radius

Palmar plate fixation of distal radial fractures is becoming a standard treatment for this common injury. Ruptures of the extensor pollicis longus tendon have been reported in 8.6% of cases after this procedure. Although palmar plate fixation has also been associated with flexor pollicis longus (FPL) tendon problems, the majority of reported cases pre-date the use of newer anatomically precontoured locking plates. In this paper seven cases of FPL rupture are presented. This complication does not appear to be unique to one type of implant. The possible aetiologies for FPL ruptures are discussed and ways to reduce the incidence of this complication are suggested.