Traumatic dislocations of the distal carpal row

TRAUMATIC

DISLOCATIONS

OF THE DISTAL

CARPAL

ROW

C. H. PA1 and D. C. WE1 From the Department of Orthopaedic Surgery, Fangliao General Hospital, Pingtung, Taiwan, Republic of China

13 patients who sustained high-energy crush or blast injury of the carpal bones were reviewed after a mean follow-up period of 30 months. These complex injuries resulted in unusual disruptions of the distal carpal row and adjacent metacarpals. Frequent involvement of the carpometacarpal (CM) joints and violation of the proximal carpal row were also demonstrated. Nine were open injuries, with the majority accompanied by significant soft tissue damage. Treatment included either closed reduction or open reduction and Kirschner wire fixation, and soft tissue procedures as indicated. In this series, the majority of the open injuries gave unfavourable functional results despite adequate carpal, alignment. Several cases had disastrous outcomes related to associated vascular injuries. Closed injuries, on the contrary, followed a relatively benign course. Nevertheless, decreased grip strength persisted in both groups for a long time. Patients with such a complex carpal injury should expect a less favourable prognosis due to the severe nature of the trauma. Journal of Hand Surgery

(British and European

Carpal dislocations of peri-lunate type, which are mostly caused by hyperextension, usually give favourable results if a stable anatomical reduction is obtained and maintained. However, carpal injuries due to a dorsal palmar crushing force apparently have different and unusual patterns of carpal derangement and clinical manifestations (Garcia-Elias et al, 1989). Accompanying soft tissue damage is fr.equent and often severe in these injuries, and the functional results in the hand are usually unpredictable (Cooney et al, 1991). This article reports our experience with 13 patients following such rare carpal injuries, including several cases with more complex patterns than those previously reported. PATIENTS

AND METHODS

13 patients with dislocations of the distal carpal row have been reviewed. They were seen and treated between 1984 and 1992, and there were nine men and four women, with ages ranging from 14 to 52 years (average of 30.8 years). The mechanisms of injury were crushing (heavy machine compression, roller press, and in a door) in 11, and one each due to an explosion and a motorcycle accident. Soft tissue injury

Open injuries were found in nine cases, of whom eight demonstrated severe damage to the skin and intrinsic muscles, leading to significant scar contracture in several cases. Vascular injury was noted in three (cases 1, 2 and S), all of which were followed by digital amputations, despite attempted vascular anastomosis in two cases. When median nerve dysfunction occurred, it resolved uneventfully following skeletal reduction without carpal tunnel release. Details of associated injuries are shown in Table 1. Skeletal injury

The classification of these carpal injuries was based on that proposed by Garcia-Elias et al (1989), i.e., axial

Volume, 1994) 19B: 5: 576-583

radial (AR) type, axial ulnar (AU) type, and combined AR and AU dislocations. Some of our cases could not be included in this system, due to the more complex patterns encountered. There were four cases which could be included in the AU type of dislocation: peri-hamate and peri-pisiform dislocation in three (cases 11, 12 and 13) and transhamate peri-pisiform dislocation in one (case lo), in which the fourth and fifth metacarpals and the dislocated hamate bone formed a unit, separate from the third metacarpal (Fig 1) . Six cases fell into the AR category. Four of these were subclassified as the peri-trapezium and trapezoid type (cases 4, 5, 6 and 7; Fig 2). Two further cases were peri-trapezium and peri-scapho-lunate dislocation (cases 8 and 9), considered to be a variant of the axial injury (Fig 3). All of the adjacent metacarpals, either the first or the first and second as a unit, were involved. Multiple CM joint dislocations were noted in five of the AR lesions. Both the radial and ulnar sides of the carpus were disrupted in three patients (cases 1, 2 and 3), which is considered to be extremely rare. However, two of these cases revealed more complex patterns of carpal disorganization with additional involvement of the capitate or combined scaphoid and capitate, which could not be simply classified as pure axial lesions (cases 1 and 2; Fig 4). All three cases had CM joint involvement.

Treatment

11 of the 13 patients were treated within 24 hours of the initial accident, either by the closed or open method. The other two cases were treated 3 and 16 days later because of delayed referral for soft tissue problems and carpal malalignment (cases 1 and 11). Initial treatment for open injuries included thorough wound irrigation with pulsed lavage and radical dtbridement of all devitalized skin, subcutaneous tissue and muscle. This was followed by skeletal reduction and

DISTAL CARPAL ROW DISLOCATION Table l-Type

of axial carpal dislocation,

Case

Age, Sex, Side

1

27, F, R

2

21, M, L

3

14, M, L

4 5 6* 7* 8 9 10 11 12* 13*

31, 33, 32, 28, 35, 52, 26, 25, 40, 37,

*: Closed injury; phalanx fracture;

M, M, F, M, F, M, M, F, M, M,

Peri-trapezium, peri-trapezoid Hamate, pisiform Capitate Peri-trapezium, peri-trapezoid Transhamate fracture Capitate, scaphoid Peri-trapezium; peri-trapezoid Peri-pisiform Peri-trapezium, trapezoid Peri-trapezium, trapezoid Peri-trapezium, trapezoid Peri-trapezium, trapezoid Peri-trapezium, peri-scapho-lunate Peri-trapezium, peri-scapho-lunate Transhamate peri-pisiform Peri-hamate, peri-pisiform Peri-hamate, peri-pisiform Peri-hamate, peri-pisiform

2Y 5Y 2Y2M 3Y3M

ORIF ORIF ORIF CREF

9

2Y6M

ORIF

10

2Y8M 8M

ORIF ORIF

Soft tissue Vascular repair Ulnar fascial flap + STSG FTSG

Vessel and tendon repair + FTSG Tendon repair + radial forearm flap

NA: Not available for follow-up; ORIF: Open reduction and internal Split-thickness skin graft; FTSG, Full-thickness skin graft.

Table 3-Treatment

CREF:

Mechanism

1 and 2

3-5

a, c, d, e

Rolling

1 and 2

3-5

a, c, d, e, g, h

Motorcycle

1

e,_i

Blast

2-4 3-5 3-5 3-5 5

4 e g, i

Crush Crush Crush Crush Crush Crush Crush Crush Crush Crush

l-5 1 1 1 1

4 4 4 4

and and and and

and and and and

2 2 2 2

b, d; e, f, h d, e, f d e

5 5 5 5 muscles;

f: Flexor

tendons;

g: Metacarpal

Clinical score

Treatment

Length of follow-up

ORIF ORIF

6 7 12 13

Associated injuries

fracture;

h: Proximal

and results of open injuries

NA 2Y3M

Case

CM dislocation

a: Ulnar artery; b: Radial artery; c: Ulnar nerve; d: Median nerve; e: Intrinsic i: Distal radio-ulnar joint; j: Traumatic amputation of fingers.

Bone

11

Metacarpals involved

Carpal dislocation

R R R R L R R L R R

Table 2-Treatment Case

associated lesions, and mechanism of injury

Pain

ROM

Grip

Comment Work

(Total)

(50)

25

5

0

20

25 25 25 25

15 25 25 25

0 10 15 0

20 20 25 15

20

15

5

20

(60)

25 25

25 25

15 5

25 15

(90) (70)

fixation;

CREF:

Closed

reduction

and external

fixation;

3 digits amputation 2 digits amputation, Adductor contracture Traumatic amputation

Thumb amputation, adductor contracture CM joint arthritis AVN of lunate Adductor release t radial forearm flap AVN: Avascular

necrosis;

STSG:

and results of closed injuries Length of follow-up

2Y6M 2Y 2Y4M 3Y Closed reduction

and external fixation.

Treatment

CREF CREF CREF CREF

Clinical score Pain

ROM

Grip

Work

(Total)

25 25 25 25

25 25 15 25

10 15 15 15

25 25 25 25

(85) (901 (80) (90)

578

Fig 1

THE JOURNAL

OF HAND

SURGERY

VOL. 19B No. 5 OCTOBER

1

Case 10. (a and b) An open transhamate peri-pisiform dislocation in a 26-year-old man after a machine crush injury. (c) Following open reduction and Kirschner wire fixation; the pisiform remains unreduced. (d) 2 years and 8 months later, there is evidence of avascular necrosis of lunate and questionable consolidation of hamate. However, the patient is free of pain, with only slightly decreased grip strength noted (90 points).

DISTAL CARPAL ROW DISLOCATION

Fig 2

Case 4. (a and b) An open peri-trapezium and trapezoid dislocation with multiple dislocations of the second, third and fourth CM joints after a heavy machine compression. The trapezium and the first and second metacarpals lie proximal and radial to the scaphoid. The trapezoid has lost its normal articulation with the scaphoid. (c) After open reduction and internal fixation. (d) A nearly normal appearance of the carpal bones 5 years following surgery. Unfortunately, weak grip strength persisted (80 points).

THE JOURNAL OF HAND SURGERY VOL. 19B No. 5 OCTOBER 1994

Fig 3

Case 9. (a and b) Peri-trapezium and peri-scapho-lunate dislocation in a 52-year-old man. The trapezium with the adjacent first metacarpal ray is almost detached from the scaphoid. The trapezoid, capitate, hamate and triquetrum as a unit show dorsal subluxation with respect to the intact scapho-lunate unit. This case was treated by the open method. (c and d) Initial skin and intrinsic muscle injuries are shown on the dorsum and the thenar part of the hand. (e) A reversed radial forearm flap has been applied to the thenar area. (f) Degenerative arthritis of the first CM joint is obvious (at 2 years and 6 months).

internal fixation using multiple Kirschner wires. Most of the open injuries were reduced through the wounds without additional incisions. Repairs of severed tendons and neurovascular structures were also performed in several cases. Significant skin defects were managed by

either primary free skin grafts or delayed vascularized flaps. Four cases of closed injuries with mild displacement of the carpal bones were treated by closed reduction and casting because the patients refused open treatment.

DISTAL

CARPAL

ROW DISLOCATION

Fig 3

(e and f) For legend please see p. 580.

A unique case with severe open crushing injury was treated by manual traction and casting because of initial marginal viability of the cutaneous tissue (case 8). Maintenance of reduction in the cast was continued for 6 to 8 weeks in both groups. Method of assessment Clinical scoring recorded pain, functional status, range of motion and grip strength measured as a percentage of the normal contralateral hand (Cooney et al, 1987). Points were accumulated and a final rating obtained as follows: excellent, 91 to 100 points; good, 81 to 90 points; fair, 65 to 80 points, and poor, less than 65 points. A clinical result was considered satisfactory with 65 or more points. RESULTS 12 of the 13 patients were followed for an average of 30.3 months (range 8 months-5 years); Table 2 and 3. There were five good results, four fair, and three poor. No-one obtained an excellent result in this series.

The presence of severe skin crushing, intrinsic muscle destruction and vascular injury resulted in stiff hands and finger amputations. This invariably led to poor results (cases 2 and 3). Another case with a poor result was noted to have severe open peri-trapezium and periscapho-lunate dislocation, with resulting CM joint arthritis (case 9). Of the four cases with fair results, three were open injuries (cases 4, 8 and 11). However, all four cases demonstrated adequate carpal alignment at follow-up (Fig 2). This lack of correlation between clinical and radiological results was thought to be due to soft tissue damage. Of the five cases with good results, three were found among patients with mild closed injuries (cases 6, 7 and 13). However, one case with open transhamate peripisiform dislocation developed avascular necrosis of lunate after 32 months, although the patient remained asymptomatic (case 10). This has been described previously (Naam et al, 1992). A common finding in this series was persistent weak grip strength, even when a painless and reasonably mobile wrist was found at the final examination.

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582

Fig 4

Case 2. (a and b) A severe injury of the wrist and hand after a motorcycle accident. The radiograph shows dislocation of scaphoid with enucleation. The capitate was deviated to the ulnar side along its central axis. There was axial radial disruption of trapezium and trapezoid with the adjacent first and second metacarpals. Comminuted transhamate fracture and multiple fracture-dislocations of the third, fourth and fifth CM joints. Additional fractures were present on the fourth metacarpal shaft, the proximal phalanx of index finger, and the radial styloid. Only the lunate, triquetrum and pisiform were not involved. Amputation of fingers were required.

DISCUSSION Carpal dislocations following crush or blast injury demonstrate rare and unusual patterns in most instances, with the majority involving the distal row of the carpus (Primiano and Reef, 1974; Garcia-Elias et al, 1985; Norbeck et al, 1987; Garcia-Elias et al, 1989). Previous reports of these injuries have mostly been case presentations, predominantly with injury to the hamate but rarely the trapezium (Duke, 1963; Gainor, 1985; Gunn, 1985; Holdsworth and Shackleford, 1987; Ogunro, 1983; Ohshio et al, 1986). Following the large series of 16 cases reported by Garcia-Elias et al (1989), these carpal injuries have been categorized separately from the more common perilunate type, and the term “axial dislocation of the carpus” has been proposed. The essential feature of this injury is in the distal row

of the carpus and adjacent metacarpals. Frequent involvement of neighbouring CM joints and less frequent violation of the proximal carpal row were also present in our patients. Several cases that revealed more complex and severe forms of carpal disruption, in which additional involvement of scaphoid, capitate or perilunate components were noted, might be classified as variant types of axial lesion (cases 1, 2, 8 and 9). These cases were thought to be caused by a combination of strong anteroposterior compression and forced hyperextension. Because of the high energy involved in producing such an injury, the severity of the associated soft tissue damage demands attention in addition to the skeletal lesions. We feel that successful management of the soft tissues is the first step toward salvage of hand function, and correct soft tissue intervention should be the pri-

DISTAL

CARPAL

ROW DISLOCATION

ority. However, when a significant cutaneous defect demands a vascularized flap, we prefer to do this as a delayed procedure. Although the primary skin cover would be preferable by means of emergency flap transfer, purely from the point of view of tissue preservation. We have used two reversed radial forearm flaps (cases 9 and 11) and one reversed ulnar fascial flap (case 2) for soft tissue cover in this series. For mild and closed injuries, early closed reduction and casting should be attempted initially. Four of our cases which were managed in this manner showed carpal bones in stable reduction in this series. Previous reports (Duke, 1963; Garcia-Elias et al, 1985) also have demonstrated several cases of similar injury which were successfully treated by the closed method. However, operative treatment should be used if either malaligned carpal bones or loss of reduction are anticipated. For open injuries, prompt open reduction and internal fixation are of value. These facilitate later procedures in complicated cases. In our patients, most of the carpal injuries could be reduced and fixed through the wound without additional incisions. In a few cases, a dorsal approach was satisfactory for skeletal reduction. In our series, good results were achieved in 75% (3 out of the 4) of the closed injury group, and in only 25% (2 out of the 8) of the open injury group. This reflects the contribution of associated soft tissue damage to unfavourable results. Even with nearly normal radiographs at the final examination, poor results were unavoidable in several cases. In our three extremely digital amputations were complex cases, multiple required despite the adequate carpal alignment obtained. In several complicated cases, thumb web and finger joint contractures followed prolonged immobilization. Therefore, in addition to vigorous and prolonged physiotherapy, soft tissue release was also required. Weak grip strength was a common finding, even 5 years after surgery, despite nearly painless and adequate range of movement of the wrist in most cases. This was noted by Norbeck et al (1987) in their three cases. Gartsman et al (1986) reported carpal arch alteration and significantly decreased grip strength after carpal tunnel release, even 20 months after surgery. In our experience and the literature (Garcia-Elias et al, 1989), the flexor retinaculum is usually disrupted with carpal arch collapse in these injuries. Therefore it is possible

583

that persistent weak grip strength after such an injury may be associated with tearing of the flexor retinaculum and alteration of the proximal carpal arch. In the present study, adequate carpal alignment at follow-up does not guarantee a good result. Associated soft tissue problems definitely influence the final outcome, and the clinical and radiographic results do not always correlate. Even with optimal treatment, some disability of the hand persists for a long time. Acknowledgement We are grateful to Professor C. Howard Tseng from Yuan’s General Kaohsiung, Taiwan, for his great assistance with writing this paper.

Hospital,

References COONEY, W. P., BUSSEY, R., DOBYNS, J. H. and LINSCHEID, R. L. (1987). Difficult wrist fractures: Peri-lunate fracture-dislocations of the &st.‘Clinical Orthopaedics and Related Research, 214: 136-147. COONEY, W. P., LINSCHEID, R. L. and DOBYNS, J. H. Fractures and dislocations of the wrist. In: Rockwood, C. A., Green, D. P. and Bucholz, R. W. (Eds): Fmctures. Philadelphia, Lippincott, 1991: Vol 1: 629-638. DUKE. R. (1963). Dislocation of the hamate bone. Journal of Bone and Joint S&g& 45s: 4: 744. GAINOR: B. J. (1985). Simultaneous dislocation of the hamate and pisiform: A case report. Journal of Hand Surgery, 10A: 1: 88-90. GARCIA-ELIAS, M., ABANCO, J., SALVADOR, E. and SANCHEZ, R. (1985). Crush injury of the carpus. Journal of Bone and Joint Surgery. 67B: 2: 286-289. GARCIA-ELIAS, M., DOBYNS, J. H., COONEY, W. P. and LINSCHEID, R. L. (1989). Traumatic axial dislocations of the carpus. Journal of Hand Surgery, 14A: 3: 446-457. GARTSMAN, G. M., KOVACH, J. C., CROUCH, C. C., NOBLE, P. C. and BENNETT, J. B. (1986). Carpal arch alteration after carpal tunnel release. Journal of Hand Surgery, 11A: 3: 372-374. GUNN, R. S. (1985). Dislocation of the hamate bone. Journal of Hand Surgery, 10B: 1: 107-108. HOLDSWORTH, B. J. and SHACKLEFORD, I. (1987). Fracture dislocation of the trapezia-scaphoid joint-the missing link? Journal of Hand Surgery, 12B: 1: 4042. NAAM, N. H., SMITH, D. K. and GILULA, L. A. (1992). Transtriquetral peri-hamate ulnar axial dislocation and palmar lunate dislocation. Journal of Hand Surgerv. 17A: 4: 762-766. NORBECK, D. E., LARSON, B.: BLAIR, S. J. and DEMOS, T. C. (1987). Traumatic longitudinal disruption of the carpus. Journal of Hand Surgery, 12A: 4: 509-514. OGUNRO, 0. (1983). Fracture of the body of the hamate bone. Journal of Hand Surmrv. _ ,_ 8: 3: 353-355. OHSHIO: I., OGINO, T. and MIYAKE, A. (1986). Dislocation of the hamate associated with fracture of the trapezia1 ridge. Journal of Hand Surgery, 11A: 5: 658-660. PRIMIANO, G. A. and REEF, T. C. (1974). Disruption of the proximal carpal arch of the hand. Journal of Bone and Joint Surgery, 56A: 2: 328-332.

Accepted: 2 December 1993 Chung-Ho Pai, MD; 436-3, Kuang-Fu Road, Pingtung 90037, Taiwan 0 1994 The British Society for Surgery of the Hand