Complex and rare fracture patterns in perilunate dislocations

Periarticular distal radius fractures and complex ligamentous injury: The role of arthroscopic evaluation

Purpose

Distal radius fractures are associated with a high incidence of concomitant soft tissue injuries, including lesions of the triangular fibrocartilage complex and intercarpal ligaments. While advanced imaging has allowed for greater identification of such tears, discerning which lesions pose a functional consequence remains a challenge for the hand surgeon. A review and guideline for arthroscopic evaluation of suspected combined injuries is presented.

Results

Arthroscopic evaluation of distal radius fractures provides several unique advantages in such instances. Articular reduction can be performed via direct visualization with improvement in step-off and gapping. Furthermore, ligamentous injuries and carpal alignment can be directly assessed and treated.

Conclusions

Subtle features of combined ligamentous trauma may be overlooked in the presence of more obvious fracture patterns. Wrist arthroscopy allows not only for a gold-standard method of evaluating of these soft tissue injuries, but also a means of treatment.

Transscaphoid Transcapitate Perilunate Fracture-dislocation with Inferior Arc Injury and Acute Ulnar Nerve Compression: A Case Report

Introduction

Perilunate dislocations and perilunate fracture-dislocations (PLFD) are relatively uncommon injuries, comprising <10% of wrist injuries. Perilunate injuries are often complicated by median neuropathy reported in 23-45% of cases, whereas there are very few reported cases of associated ulnar neuropathy. Combined greater arc and inferior arc injuries are also rare. We report an unusual PLFD pattern with associated inferior arc injury and acute ulnar nerve compression.

Case Report

A 34-year-old male sustained a wrist injury after a motorcycle collision. Computed tomography scan revealed a trans-scaphoid, transcapitate, perilunate fracture-dislocation, and a distal radius lunate facet volar rim fracture with radiocarpal subluxation. Examination revealed acute ulnar neuropathy without median neuropathy. He underwent urgent nerve decompression and closed reduction, followed by open reduction internal fixation the next day. He recovered without complication.

Conclusion

This case emphasizes the importance of a thorough neurovascular examination to rule out less commonly seen neuropathies. With up to 25% of perilunate injuries misdiagnosed, surgeons should have a low threshold for advanced imaging in high-energy injuries.

Arthroscopic Treatment of Capitate Nonunion: A New Technique

Isolated fractures of the capitate are very rare which means that their nonunion is even rarer. Repair techniques have always been performed by open surgery which may result in loss of mobility due to the capsulotomy. The typically used surgical techniques such as arthrodesis of the carpal or wrist bones can have irreversible consequences on range of motion. No arthroscopic technique has ever been described for this condition. Here, we describe a case of isolated capitate nonunion without ligament tears or other carpal fractures in a 21-year-old male, following a capitate fracture 10 years prior. We describe our arthroscopic treatment technique for this capitate nonunion.

Pancarpal dissociation, a very rare type of injury: A case report

RATIONALE

Pan-carpal dissociation is very rare injury and there is little information as to diagnosis, treatment, and prognosis of this injury.

PATIENT CONCERNS

A 35-year-man presented to our hospital with severe pain and swelling of the left wrist and forearm after slipping and falling while riding a motorcycle.

DIAGNOSIS

The wrist simple radiographs demonstrated unrecognizable severe fracture-dislocation of the carpal bones concomitant with fractures of the radioulnar shaft. Three-dimensional computed tomography revealed a capitate fracture-dislocation, as well as hamate dislocation, lunotriquetral (LT), and scapholunate (SL) dissociation. These findings suggested pan-carpal dissociation.

INTERVENTIONS

To prevent compartment syndrome, fasciotomy, carpal tunnel release, and open reduction and plate fixation for both bone fracture were performed first. Then, for pan-carpal dissociation, the capitate, carpometacarpal joint (CMCJ), and hamate were reduced and fixed first. Then, the SL, LT, and other intercarpal ligaments were repaired. Finally, additional trans-carpal pins to reinforce the ligament repair and 2.0 mm plate to buttress the third CMCJ were fixed. The patient was instructed to begin gentle range of motion exercises of the wrist with pins from four weeks after surgery and all pins were removed at six weeks postoperatively.

OUTCOMES

12 months after the operation, the patient exhibited almost full range of motion with mild pain with VAS (Visual analogue scale) 1-2 at rest and VAS 3-4 with effort. Quick DASH (the disabilities of the arm, shoulder and hand) score was 25 and modified Mayo score was 70. The radiographs demonstrated union of the radioulnar shaft, and the carpal bone alignment was successfully maintained.

LESSONS

Pan-carpal dissociation can be diagnosed in patients with capitate fracture-dislocation, hamate dislocation, LT, and SL dissociation. This pattern of injury is very rare and the authors recommend reduction and fixation of the distal carpal row, followed by the proximal row to facilitate an easy approach to the distal carpal row. Although it is very severe injury, rigid anatomical fixation and an early rehabilitation can lead to favorable functional outcomes.

Imaging evaluation of traumatic carpal instability

PURPOSE

To review the epidemiology, pertinent wrist anatomy, classification system, and emergent imaging evaluation of carpal instability with a focus on radiographic assessment of instability.

METHODS

A review of current literature on carpal instability was performed with summary presentation of carpal instability epidemiology, carpal anatomy, imaging evaluation, and classification with imaging evaluation focused on diagnosis in the emergency setting.

RESULTS

Carpal instability is a common pathology in falls on outstretched hand and is likely underdiagnosed due to instability being occult or demonstrating subtle malalignment on static imaging of the wrist. While there is a complex network of intrinsic and extrinsic ligaments contributing to carpal instability, a detailed knowledge of these ligaments is not necessary for radiologists to make an accurate diagnosis in the emergency setting, as identification and classification of carpal instability is based on identification of carpal malalignment patterns on radiography as opposed to identification of specific ligament injuries on advanced imaging. The Mayo classification is the most widely used classification system, which divides carpal instability into four categories: dissociative, non-dissociative, complex, and adaptive. Understanding this classification system allows radiologists to successfully classify almost all carpal instability injuries they will encounter, even in the setting of unusual or rare instability patterns.

CONCLUSION

In working with the treating clinician, it is essential that the emergency radiologist is comfortable with identifying and classifying carpal instability. This will ensure prompt treatment of seemingly benign injuries and those that require intervention, surgical or otherwise, improving the likelihood of a good outcome.

The treatment of perilunate ligament injuries in multiply injured patients

PURPOSE

Perilunate injuries are rare, severe injuries of the carpus. They can present as isolated injuries or in the poly-traumatised patient. This is the first documented series of these injuries treated in a Major Trauma Centre. The aims were to assess the management, treatment algorithm and outcomes, of perilunate injuries in our department, review whether concomitant polytrauma affected those outcomes and identify if delay to definitive treatment had a significant effect on overall outcome.

METHODS

Perilunate injuries admitted to the Royal London Hospital between Oct 2011 and March 2016 were identified. All definitive surgical procedures were performed by the senior author; hand therapists supervised patient rehabilitation. Outcomes were assessed by Mayo Wrist and QuickDASH scores.

RESULTS

We identified 23 perilunate injuries (22 patients). There was an associated nerve injury in 10 cases with other system injuries present in 12 cases. At final review, the mean carpal height ratio was 0.56, Mayo Wrist score was 81 and QuickDASH score was 16.4. There were no differences when comparing the outcomes of patients who had early against those with more delayed definite treatment or when comparing patients with isolated wrist injuries against polytrauma patients.

CONCLUSION

Satisfactory outcomes can be achieved, even in the presence of other injuries, if initial treatment is prompt and follows a clear management protocol. Prompt early reduction and neurological decompression followed by subsequent accurate definitive fixation leads to good outcomes. A delay of definitive fixation of up to 18 days does not appear to have a deleterious effect on outcome.

The Vascular Anatomy of the Capitate: New Discoveries Using Micro-Computed Tomography Imaging

PURPOSE

To study the intraosseous 3-dimensional microvasculature of the capitate bone using a novel high-resolution micro-computed tomography (μCT) imaging technology, and to examine the blood supply as it relates to the most common fracture types.

METHODS

Ten cadaveric wrists were injected with a lead-based contrast agent. The capitates were harvested and imaged using a μCT scanner. The intraosseous vascularity was incorporated into a 3-dimensional image. We measured the vascular pattern as well as the vessels' cross-sectional area, number, and distribution. An average capitate fracture line was calculated using clinical data from 22 patients with capitate fractures. The fracture line was projected on the representative capitate to assess its relation with the nutrient vessels' entry points.

RESULTS

The capitate is a well-vascularized carpal supplied by dorsal and volar vascular systems that anastomose in 30% of cases. There was no predominance of one vascular system over the other. Most vessels enter the capitate at the distal half and supply the proximal pole in a retrograde fashion. In addition, most specimens (70%) also had at least one vessel entering the proximal pole through the volar capitate ligaments and supplying the proximal pole directly. The average fracture line had an oblique orientation, and 90% of the specimens had a blood vessel entering proximal to that line.

CONCLUSIONS

This μCT vascular study further verifies that the capitate receives most of its vasculature in a retrograde fashion, but the study also shows that most capitates have vessels supplying the proximal pole directly. These findings might explain why most capitate waist fractures do not progress to proximal pole avascular necrosis.

CLINICAL RELEVANCE

This study characterizes the microvasculature of the capitate and might shed light on processes involved in bone healing and the etiology of capitate avascular necrosis.

Spontaneous flexor tendon rupture secondary to capitate non-union. A case report and review of literature

Rupture of the flexor digitorum profundus and superficialis tendons of the index finger secondary to non-union of the capitate has not yet been reported to our knowledge. We describe the case of a 48-year-old man with rupture of both flexor tendons of the index finger that occurred 15 years after a capitate fracture. The patient was completely asymptomatic before the rupture. Tendon reconstruction was performed using the palmaris longus. One year after surgery, the patient had acceptable range of motion and was pain-free.

Capitate Fractures: A Review of 53 Patients

PURPOSE

To describe the demographics, diagnosis, management, and outcomes of capitate fractures in the adult and pediatric population treated in our institution.

METHODS

We performed a retrospective chart and radiographic review of 53 patients with capitate fractures treated in our institution between 2002 and 2015. Patients' demographic characteristics, mechanism of injury, management including surgery-related data, and outcomes, including complications, were recorded. A radiographic evaluation of the location and pattern of the fracture was performed.

RESULTS

Capitate fractures were prevalent in young males and older females. Fracture location was variable with 9 different locations; in addition 80% of patients had an associated fracture in the wrist or hand. The most common fracture pattern was the transscaphoid, transcapitate perilunate dislocation. Most diagnoses were made with the aid of advanced imaging. Within this series, there was only 1 case (4%) of fracture nonunion and there were no cases of avascular necrosis of the proximal pole in limited follow-up. Isolated capitate fractures were significantly more common in children. In addition, children had better functional outcomes than adults.

CONCLUSIONS

This series provides updated information on this rare injury. Nonunion of the capitate, which was previously described as the most common complication, was rare in this cohort.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Carpal fractures other than scaphoid

Carpal fractures are uncommon, but if missed, can lead to morbidity and loss of function, especially in an athlete. Early diagnosis through physical examination, plain radiographs, and possibly advanced imaging is paramount. Treatment is specific to each fracture type, and return to play varies with each clinical scenario. This article organizes current knowledge of these potentially difficult fractures with a table of diagnoses and treatment guidelines.

Headless bone screw fixation for combined volar lunate facet distal radius fracture and capitate fracture: case report

We report a case of concomitant fractures of the volar lunate facet of the distal radius and capitate body. Surgical fixation was achieved with open reduction internal fixation using headless compression screws for both fractures. Because of the nature of complications seen after both operative and nonsurgical management, these fractures warrant particular attention.

Carpal fractures

Carpal fractures are exceedingly rare clinical entities and are often associated with concomitant injuries. In this review, we focus on fractures of the carpus, excluding the scaphoid, and provide an update on the current consensus as to mechanism, diagnosis, management, outcomes, and complications after such injuries.

Post-traumatic carpal instability

The complexity of the carpus explains the difficulty treating carpal injuries. Lesions are dominated by perilunate dislocation, scapholunate dislocation, and scaphoid fractures. The other injuries are trivial. Symptoms include pain and loss of wrist strength, reversible for an acute and well-treated lesion. Too often, these ligament injuries are diagnosed late. For delays longer than 6 weeks, ligament repair is ineffective. These old, complex lesions are potentially highly arthritic in the radiocarpal and mediocarpal joints. Improvements in wrist surgery have mitigated these chronic lesions. Various surgical techniques can preserve a functional wrist; wrist arthrodesis is no longer the only solution for these arthritic wrists. Over the past decade, arthroscopy has contributed to better understanding the injuries of the carpus as well as to better healing them. For acute or chronic ligament injuries without degenerative osteoarthritis, arthroscopy is the treatment of the future. This technique involves a long learning curve and the various arthroscopic techniques must be validated.

Initially unrecognised lunate dislocation as a cause of carpal tunnel syndrome

A patient was admitted reporting tingling pain and numbness in the right hand. Neurological examination--including nerve conduction studies--diagnosed carpal tunnel syndrome. Operative carpal tunnel release was performed without complications. Four months postoperatively the otherwise healthy patient presented again due to persistent complaints, although preoperative symptoms had improved. On this occasion, the patient reported loss of strength accompanied by rigidity in the wrist. Clinical examination showed some swelling adjacent to the operation wound. A postoperative ganglion cyst was suspected and a conservative treatment option--splinting the wrist--was chosen. Four weeks later the patient presented again with further swelling and increasing rigidity of the wrist. Surgical intervention was planned. Preoperative plain radiographs of the wrist revealed chronic palmar dislocation of the lunate to be the cause of the symptoms in our patient. Radiological signs of scapholunate advanced collapse arthritis (SLAC wrist) were also observed.