Narrow Results

As the distal radius fracture is one of the most commonly encountered upper limb injuries, the aim of this study was to provide a quick and easy method to aid in the assessment of fractured wrists, both pre- and post-fixation, by utilising the relationship of the radial shaft and the lunate.

A retrospective analysis on 100 consecutive patients with normal wrist radiographs was performed. The results demonstrated that the variations of radiolunate anatomy followed a normal distribution. The normal anatomical relationship was then described.

A second part to the study consisted of reviewing our method of radiocarpal analysis on a cohort of patients who had sustained a distal radius fracture. Carpal alignment pre- and post-fixation was measured, with the results demonstrating that by using this assessment method, it was possible with a quick glance of the radiograph, to determine whether satisfactory correction of the fracture had been achieved.

The purpose of this study was to assess vascularity of the lunate by number of foramina and radiography of vessels of the wrist. The genesis of lunatomalacia requires some vascular risk and mechanical predisposition. The findings were correlated with the cause of Kienböck's disease. The vascular foramina were more than two in 91.33% of the lunate. The lunate had consistent dorsal and palmar branches from radial artery. The additional branches from anterior interosseous artery in 72.22% and a branch of palmar inter carpal arch in 69.44% cases contributed in arterial anastomosis on palmar aspect of lunate. The dorsal blood supply was found by anterior interosseous artery in 85.71% of specimens and dorsal branch from dorsal intercarpal arch in 50% of specimens. The blood supply of lunate comes along with various ligaments which may be disrupted due to trauma or strain leading to avascular necrosis. The present observations are suggestive of rich blood supply of lunate in comparison of other investigations. Therefore Kienböck's disease is less common in northern India.

Osteochondroma rarely develops from the carpal bones. We report a first case in which a dorsal osteochondroma of the lunate caused attritional rupture of the tendon of the extensor indicis proprius and a tendon of the extensor digitorum communis of index finger.

Kienböck's disease is known for its difficulty in being diagnosed and treated at early stages; option treatments are few and most of them quite aggressive. The author describes his experience with arthroscopic assisted lunate bone grafting. Three patients with diagnosis of stage I avascular necrosis of the lunate (average age: 45 years), were treated. Before surgical procedure, the patients underwent to a conservative treatment. After harvesting the bone graft from the volar surface of the radius, arthroscopic bone grafting was performed.

At an average follow-up of 13.5 months (9–15), all the patients show a normal density of the lunate and no arthritic changes in radiographs. The MRI confirmed the lunate vascularity.

The number of patients is definitely small, due also to the rarity of the disease and the difficulty in diagnosis, but, despite the very high learning curve, could be the proper first choice of treatment.

Simultaneous avascular necrosis of multiple carpal bones is rare. Concomitant avascular necrosis of scaphoid and lunate has been reported only once. We report one more case of this rare condition which can be a cause of wrist pain. Steroid intake is a known risk factor for avascular necrosis but in our case the patient had been taking herbal medicines for joint pain the composition of which was not known. Probably the presence of steroid in these medicines was the cause of avascular necrosis in this case.

Kienböck disease is a disorder of impaired lunate vascularity which ultimately has the potential to lead to marked degeneration of the wrist and impaired wrist function. The aetiology of the avascular necrosis is uncertain, but theories relate to ulnar variance, variability in lunate vascularity and intraosseous pressures. Clinical symptoms can be subtle and variable, requiring a high index of suspicion for the diagnosis. The Lichtmann classification has historically been used to guide management. We present a review of Kienböck disease, with a focus on the recent advances in assessment and treatment. Based on our understanding thus far of the pathoanatomy of Kienböck’s disease, we are proposing a pathological staging system founded on the vascularity, osseous and chondral health of the lunate. We also propose an articular-based approach to treatment, with an arthroscopic grading system to guide management.

We report two rare cases of existing or worsening symptoms due to Kienböck’s disease after distal radius fracture (DRF). During examination, radiographs show changes in the lunate bone; there was persistent wrist pain after treatment for DRF. In each case, surgeries were performed: A combined therapy (bone marrow transfusion, bone peg graft, external fixation, and low intensity pulsed ultrasound) for one, as well as carpal coalition for another. The etiology of these case presentations suggest that a compression fracture of the lunate due to a DRF resulted in softening and sclerosis.

Extensor tendon rupture of the finger is a very rare complication of Kienböck’s disease. However, advanced Kienböck’s disease can cause an attritional rupture of extensor tendons due to displaced lunate fragment. An extensor tendon of the thumb is frequently damaged in the distal radial fracture, and an extensor tendon of the fifth finger is mainly ruptured in arthritis of distal radio-ulnar joint. On the other hand, the extensor tendons of the 2^nd, 3^rd and 4^th fingers are usually ruptured in advanced Kienböck’s disease. We report two elderly patients diagnosed with advanced Kienböck’s disease after non-traumatic rupture of extensor tendon of the fingers. Since the extensor tendon rupture in Kienböck’s disease present as a loss of active extension of metacarpophalangeal joint in the central fingers, these patients should undergo imaging of the wrist joints to ascertain concomitant Kienböck’s disease.

Background: The etiology and natural history of Kienböck’s disease remain unclear. Traditionally it has been defined as avascular necrosis of the lunate. The authors tried to demonstrate different tissue distribution, the area ratio of necrotic tissue and vessel counts inside the whole Kienböck lunate to reveal a dynamic process of the lunate collapse.

Methods: Five lunates from patients with stage III Kienböck’s disease and one cadaveric lunate not involved by Kienböck’s disease were sampled. They were sectioned, H&E stained, and evaluated. The thickness of trabecular bone and the area of necrotic tissue were measured with Image-Pro Plus. The number of vessels was counted manually.

Results: In the normal lunate, the bone trabeculae showed a uniform distribution with fatty marrow filled the interspace between the trabeculae. In the lunates with Kienböck disease, the trabeculae fracture and necrosis located in the central part with massive fibrous granular tissue proliferation. There were also some chondroid metaplasia at the palmar and dorsal ends. The trabeculae of the lunates of the Kienböck’s disease [0.188 mm (0.153 mm, 0.236 mm)] was significantly thicker than the normal lunates [0.146 mm (0.124 mm, 0.164 mm)]. The necrosis was localized around the fracture sites instead of the whole lunate. The mean necrosis area only accounts for 16.3% ± 8.9% of the whole section. Such kind of focal necrosis is quite similar to those around the traumatic fracture ends of other bones. Even in stage III Kienböck lunates, the vessels are quite abundant (221 ± 42 in one sagittal section), while the vessels inside the normal lunate were 352 ± 28.

Conclusions: There is neither massive nor obvious generalized avascular bone necrosis in our histopathology observations. The focal necrosis and vessel damage were more likely associated with the broken trabeculae inside the lunate. Based on our histopathology observations, we suggested that the progressive process of Kienböck’s disease could be described as lunate nonunion advanced collapse instead of avascular necrosis.

Background: Positive ulnar variance (UV) may be associated with a higher incidence of ulnar impaction syndrome (UIS). However, neutral and/or negative UV has also been associated with the development of UIS; therefore, other risk factors may be involved. The purpose of this study was to compare radiological bone morphology in patients with UIS and asymptomatic controls.

Methods: Between 2009 and 2018, posteroanterior wrist radiographs of 47 wrists in 45 patients diagnosed with UIS were compared with those of 163 wrists in 93 asymptomatic patients from the control group. The following parameters were obtained: ulnar variance (UV); ulnar head top-fovea distance (UTFD); capitate–triquetrum distance (CTD); radio-lunate distance (RLD) and lunate coverage ratio (LCR). The morphology of the lunate was classified based on the absence (type I) or presence (type II) of a medial facet that articulates with the hamate. The radiographic parameters and lunate types were compared between the two groups. We then divided the groups into two subgroups: the positive UV subgroup and the neutral/negative UV subgroup. In each subgroup, the radiographic parameters and lunate types were compared between the UIS and control groups.

Results: In the UIS group, the UV and UTFD were significantly increased compared to those in the control group. The proportion of type II lunates was significantly higher in the UIS group than in the control group. In addition, the type II lunate was more common in the UIS group in both the positive UV and negative UV groups.

Conclusions: Our study suggests that in addition to positive UV, ulnar head morphology with an increased UTFD and type II lunate morphology may be associated with the development of ulnar impaction syndrome.

Level of Evidence: Level III (Diagnostic)

Background: We report medium-term results in our case series of patients with Kienböck disease receiving a pyrocarbon lunate replacement (Integra, Smith and Nephew, Watford, UK).

Methods: Patients with Kienböck receiving a pyrocarbon lunate between September 2012 and November 2020, with stage 3b and above were included. Patients were staged preoperatively with radiographs and MRIs. Pre- and postoperative visual analogue scores and movement were documented. Postoperative radiographs were obtained at 6 weeks, 6 months and 1 year.

Results: Seven patients were identified, all female, with a median age of 28.0 years. All but one had 3b disease and the median follow-up was 2 years (range 13–112 months). A mean 9/10 preoperative VAS score improved to 1/10 by 3 months postoperatively (p < 0.001, paired t-test). No major complications were seen, and implants were stable radiologically.

Conclusions: A semi-constrained pyrocarbon lunate can provide good results for patients with advanced Kienböck’s disease, offering an alternative to proximal row carpectomy salvage surgery.

Level of Evidence: Level IV (Therapeutic)

Scaphoid lunate advanced collapse (SLAC) is the most frequently encountered cause of wrist osteoarthritis. Proximal row carpectomy (PRC) and four-orner arthrodesis (4CA) are the two main surgical options to address it. Three three-corner arthrodesis (3CA) was introduced in 1997 as an alternative to PRC and 4CA. It is a motion preserving midcarpal arthrodesis easier to perform than 4CA, for which the literature has documented satisfactory outcomes and low complication rates. We report a case of a SLAC wrist treated with 3CA complicated by postoperative osteonecrosis of the lunate. To our knowledge, this complication has not been previously reported. Our patient developed osteonecrosis of the lunate 1 year after 3CA despite a good consolidation of the arthrodesis. In this case study, we discuss reasons this may have occurred, the aetiology of which is likely multifactorial. We are reporting this case to inform surgeons of this potential complication after 3CA.

Level of Evidence: Level V (Therapeutic)

Background: We treated distal radius fractures (DRFs) beyond the watershed line without fracture of the lunate volar rim using a volar locking plate (VLP) and report the radiological and clinical outcomes at least 3 years after surgery.

Methods: In 41 consecutive patients between January 2012 and August 2017, the fragment was composed of the radial styloid process (distal to the watershed line) and the lunate volar rim was intact. We evaluated demographic factors, radiological features and radiological/clinical outcomes at the final follow-up.

Results: Twenty-nine patients were followed and evaluated. The mean follow-up period was 5.7 years. The mean patient age was 52.7 years and 24 patients had intracapsular intra-articular fractures. The fracture line was present in the lunate fossa in all patients. Twenty patients were classified as Soong grade 2, and five and four patients were grades 1 and 0, respectively. No radiological parameter (volar tilt, radial inclination, step-off and ulnar variance) was significantly different between the affected and contralateral normal sides. The mean visual analogue scale pain score and Disabilities of the Arm, Shoulder and Hand score, as well as the range of movement of the wrist, were not different between the affected and contralateral normal wrists. Finally, the grip strength on the affected side was 92% of the contralateral value. Major complications, such as nonunion, malunion and tendon rupture, were absent.

Conclusions: DRFs distal to the watershed line with an intact lunate volar rim are rare and easy to miss. Careful inspection of 3D-CT images is necessary to determine these injuries, and the optimal choice for proper fixation of the fragment amongst the commercial VLPs would result in satisfactory radiological and clinical outcomes.

Level of Evidence: Level IV (Therapeutic)

Background: The most common types of wrist dislocation are trans-scaphoid lunate dislocation (TLD) and trans-scaphoid perilunate dislocation, in which the lunate and proximal scaphoid are dislocated through the midcarpal joint. There is another rare type of dislocation in which the proximal carpi are dislocated through the radiocarpal joint. The purpose of this study is to examine the clinical features of this type of dislocation.

Methods: Six cases of the proximal carpal fracture dislocation via the radiocarpal joint were retrospectively reviewed. All patients underwent open reduction and internal fixation with the ligament reconstruction. A Mayo wrist score was assigned to each patient based on the assessment of pain, functional status, range of motion and grip strength at the last follow-up. Clinical subjective evaluation of function and pain was assessed using the patient-rated wrist evaluation (PRWE) method.

Results: All patients were male and injured with a median age of 33.5 years. The median follow-up period was 10 months. There were three types of dislocations: Scaphoid fracture dislocation, TLD and scaphoid-lunate dislocation. All patients had satisfactory results with an average PRWE of 7.2 ± 4.7. The preoperative VAS was 6.7 ± 1.0 and the postoperative VAS was 0.7 ± 0.7 (p < 0.01). Postoperative grip strength accounted for 89.2% ± 9.8% of the contralateral side; the Mayo wrist score averaged 90.0 ± 6.5, with four patients obtaining excellent and two good results.

Conclusions: Fracture dislocation of the proximal carpal bones through the radiocarpal joint is an independent type of wrist dislocation that tends to occur in young men with high-energy impact. The wrist is most often injured in a pronation hyperextension position. If treatment is timely and appropriate, the prognosis is quite good.

Level of Evidence: Level IV (Therapeutic)

Isolated unilateral absence of lunate is an extremely rare condition with only one such case reported in English literature so far. The rarity of this condition can lead to diagnostic dilemma, especially if patient has an old history of trauma or surgery around the wrist, leading to unnecessary intervention and difficulty in ensuring a good surgical outcome. We present such a case and discuss the clinical pointers to the diagnosis of this condition.

Level of Evidence: Level V (Therapeutic)