Unstable fractures of the metacarpals

Unstable Fractures o[ the Metacarpals--Douglas W. Lamb, Peter A. Abernethy, Peter A. M. Raine

U N S T A B L E F R A C T U R E S OF T H E M E T A C A R P A L S A M e t h o d of T r e a t m e n t by Transverse, Wire Fixation to, Intact Metacarpals DOUGLAS W. LAMB, P E T E R A. A B E R N E T H Y , P E T E R A. M. RAINE, Edinburgh Sixty-six patients with fractures which had been treated by this method form the basis of this study. These patients were part of a larger group of approximately 800 patients presenting to the Hand Clinics of the Royal Infirmary and Western General Hospital, Edinburgh with metacarpal fractures over a five year period from 1966 to 1970. Approximately 50 per cent of these patients had fractures involving the fifth metacarpal. Although a similar method of treatment can be utilised for Bennett's fracture such cases were not included in this review. Of the sixty-six patients, thirty-two were seen and examined. The case notes and radiographs of the remaining thirty-four patients, who failed to attend, were available for study. DETAILS OF METHOD OF TREATMENT

After assessment of the instability of the fracture and a decision to fix internally, the patient is admitted. Under general anaesthesia the displacement is corrected by manipulation and Kirschner wires are introduced percutaneously at 90 ° to the metacarpal shaft under X-ray control to fix the fragments of the fractured metacarpal to an adjacent metacarpal. The insertion of the K wires by this closed technique is quite safe as no vital structures lie on the same plane as the bones themselves. It is stressed that it is an important part of the technique to introduce the wires by power drill and not by hand. The wires are cut off subcutaneously. In some fractures, particularly those more distal with angulation of the metacarpal head, only one wire through the distal fragment may be required. In most other fractures as a general rule, two transverse wires, one in each fragment, are used. It may be necessary to use two or more wires in one or other fragment if there is any doubt about stability. In the rare case when reduction cannot be obtained by manipulation, open reduction followed by the same method of fixation, can be used. The majority of patients a r e discharged from hospital within twenty-four hours of operation, and the wires are removed later under local anaesthetic. CLINICAL DETAILS There were fifty-seven male and nine female patients~ The right hand was affected in fifty-two. TABLE 1

Age Group No. of patients

10-20 18

AGE RANGES

20-30 25

30-40 11

40-50 8

50-60 4

In fifty cases there was a single fracture. In the remaining sixteen there was a combination of multiple injuries. The details are shown in Table 2. The Hand--Vol. 5

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Unstable Fractures o/ the Metacarpals--Douglas W. Lamb, Peter A. Abernethy, Peter A. M. Raine

TABLE 2

BONE I N V O L V E D A N D N U M B E R OF F R A C T U R E S

Single fractures:

Multiple fractures:

4 2 8 36 2

2nd Metacarpal 3rd Metacarpal 4th Metacarpal 5th Metacarpal 2nd and 3rd Metacarpals 2nd, 3rd and 4th Metacarpals 3rd, 4th and 5th Metacarpals 4th and 5th Metacarpals

1

2 11 66

In fifty-two the injury was simple. There were fourteen compound injuries (Table 3). In two of these there was skin loss requiring skin replacement and in two cases there was associated extensor tendon damage. TABLE 3

T Y P E OF I N J U R Y

Occurring with single fracture Occurring with multiple fractures Total

Simple 42 10

Compound 8 6

52

14

In thirty-eight cases there was extensive post-traumatic swelling of the hand necessitating compression bandaging or elevation. This included twelve out of the sixteen multiple fractures. Table 4 indicates the site at which the fracture occurred, the type of fracture, and the displacement noted at initial radiographic examination. TABLE 4

SITE, C O N F I G U R A T I O N A N D D I S P L A C E M E N T O F F R A C T U R E i

Configuration of Fracture Line

Site of Fracture Total

Displacement of fracture Transverse Oblique Comminuted Neck

Antero-Posterior angulation Antero-Posterior and lateral angulation Lateral angulation Shortening Antero-Posterior angulation and shortening Undisplaced 44

Shaft

31

2

0

18

15

33

9 0 0

2 2 5

1 0 1

5 1 1

7 1 5

12 2 6

1 6

3 0

0 3

2 0

2 9

4 9

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The Hand--Vol. 5

Unstable Fractures of the Metacarpals--Douglas W. Lamb, Peter A. Abernethy, Peter A. M. Raine

In the sixty-six patients, fifty-seven were treated by closed reduction and internal K-wire fixation. The remaining nine required open reduction and internal fixation but in five of these, the injury was already compound. POST-OPERATIVE M A N A G E M E N T

In thirty-five patients, the hand was immobilised in a boxing-glove type of compression bandage with the metacarpophalangeal joints flexed fully. Twentyfive of these required a period of elevation of the limb in bed post-operatively, but only eleven remained in hospital longer than twenty-four hours and in some cases, this was occasioned by the need for treatment of other injuries sustained in the initial accident. The bandage was removed in all cases within one week of injury and operation. Twenty-eight patients were instructed to mobilise the hand by active movement following operation and all were discharged within twenty-four hours without supportive bandaging but after a short period of elevation of the limb in nineteen. A further three patients had additional external splintage using a volar applied Zimmer aluminium splint with the metacarpophalangeal joint of the affected ray immobilised at 90 deg. In each case the limb was elevated post-operatively but two of the patients were discharged within twenty-four hours. In these three cases the splint was maintained for one week post-operatively. In retrospect this splintage was probably unnecessary. INCIDENCE OF INFECTION In four cases infection occurred at the site of introduction of the K-wire in what had been a simple closed fracture. In three cases, a minimal local infection occurred which did not influence the management of the fracture~ The wire was removed routinely at three weeks and clinical and radiological union occurred within one month from the time of injury in each case. In the fourth patient, an abscess developed at the site of introduction of the wire which required drainage a week following operation and removal of the wire after a further week. Union of the fracture occurred within six weeks of the injury and full function was attained subsequently. In no case was there any development of osteomyelitis. U N I O N OF THE F R A C T U R E

In fifty-seven patients clinical and radiological union occurred within one month from the time of injury. In the remaining nine, union occurred shortly thereafter. There was no incidence of delayed union or non-union. The majority of the wires were removed within four weeks of the injury and all had been removed by six weeks. In one case a fragment of wire broke off and remained embedded in the metacarpal without symptoms. P E R I O D OF R E C O V E R Y F R O M I N J U R Y

This period was assessed as the time taken to resume normal function of the hand at work, home or in sporting activities and is shown from the cases reviewed in Table 5. The H a n d ~ V o l . 5

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Unstable Fractures of the Metacarpals--Douglas W. Lamb, Peter A. Abernethy, Peter Ar M. Raine TABLE 5 i

TIME TO RESUMPTION OF FULL ACTIVE USE i

i

No. of cases

2 weeks 2

4 weeks 6

6 weeks 6

Over 6 weeks 18

In the thirty-four cases not seen for review, a study of the case notes showed that in only seven was the date of return to work recorded. In all cases however, the patients had been discharged with what is recorded as full function of the hand. All patients were discharged from attendance at the Hand Clinic within two months of injury. A S S E S S M E N T OF RESULTS Thirty-two patients were seen for review. Each patient was assessed on two counts:--

Subjective: Any pain or feeling of weakness; Objective. In the subjective assessment eighteen patients "had no symptoms. It was striking that in only four of these was there any objective a6normality, wherea~ in the, other fourteen patients, who had some pain or weakness or a combination of t h e tWo, ten had some residual deformity at the fracture site as assessed either clinically or radiologically. The objective assessment by one of the authors (P.A.M.R.) was based on the following criteria: Cosmetic appearance at the fracture site e.g. prominence, rotation, recession. As already stated in the subjective assessment there is a close relationship between restoration of normal anatomy and the incidence of symptoms. E x t e n s o r lag. A lag to extension was found in only four patients-:-:in each case less than 20 degrees. P o w e r o / g r i p . This was obtained by compression of an inflated sphygmomanometer cuff to a pressure of between 15 and 20 mm of Hg. An average of three readings with each hand was taken. A figure of percentage reduction in power of grip of the injured hand relative to theother hand was obtained. By this test twenty-one had a normal grip. Eleven had reduced power three by less than 5 Fer cent. No obvious cause for the reduced power grip could be found in eight patients. In the remaining three cases good cause was found. In one an associated median nerve injury. In one, associated extensor tendon damage and in the third, reduced mobility at the metacarpophalangeal joint of the affected metacarpal. Spread-Grip Ratio. Points were marked on the skin on an axial line through the metacarpal heads on the radial aspect of the second metacarpal head and on the ulnar aspect of the fifth metacarpal head. The distance between these points was then measured firstly with the fingers widely spread in extension and secondly with the hand tightly clenched in the grip position. The two figures were then related as a spread-grip ratio. Measurements were taken for each hand and comparison of the spread-grip ratios afforded a figure of percentage reduction in spead-grip ratio of the injured hand relative to the other hand. By this test twenty-three were normal but nine had a reduction although all were less than 10 per cent. 46

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Unstable Fractures of the Metacarpals--Douglas W~ Lamb, Peter A; A bernethy, Peter A. M. Raine

This test produced results closely related to the power of grip. Of the twenty-one patients with normal grip, sixteen had a normal spread-grip ratio. Of eleven patients With weak power of grip five had a decreased spread-grip ratio. However these five patients had an average loss of power of 40% contrasted with an average loss of power of 10% in the six patients with normal spread-grip ratio. O t h e r F e a t u r e s . A minor flexion contracture of the proximal interphalangeal joim of the affected finger was noted in three cases and two of these were cases where a splint had been utilised as additional immobilisation (on review probably unnecessary) for just a week, DISCUSSION

Stable fractures of the metacarpals, being well splinted by adjacent metacarpals and the interossei, seldom require any treatment other than early active movement of the. fingers. Some may require additional control of oedema by elevation and compression bandaging of the boxing glove type. Unstable fractures are relatively rare and were assessed on cliflical and radiological grounds in the series of 800 fractures as just over 8%. Most surgeons in treating unstable metacarpal fractures use some form of external support usually plaster of Paris or splintage, but this has the decided disadvantage of limiting function of the hand and joint movement. Joint stiffness, sometimes irreparable, may result. External splintage is particularly inappropriate when there are multiple fractures complicated by severe swelling or where there is skin loss. In these circumstances internal fixation of the metacarpal fractures is best suited. Many surgeons have described longitudinal or oblique K-wire fixation, Milford (1971) considers single oblique K-wires to be the preferable method of treatment where internal fixation is required. L. D. Howard, in his excellent instructional course booklet on the management of fractures of the small bones of the hand, also gives preference to this method. In our experience it has proved difficult to insert the K-wire satisfactorily in this way and the fixation has been less stable than in the way we describe. In fact, Howard advises additional external splintage. Very little mention has been made in the literature of this method of transverse wire fixation. Bunnell (5th edition 1970) mentions the method briefly quoting the original paper by Berkman and Miles (1943) but gives no results. Furlong (1957) describes this as a possible way of treatment in unstable uncontrolable fractures of the fifth metacarpal neck but makes no reference to its use in unstable shaft fractures. James (1966) in a review of the treatment of fractures of the hand recommends the use of transverse K-wire fixation when there is instability of the metacarpal fracture. No mention is made in the majority of standard textbooks on the treatment of fractures and operative orthopaedics. Two papers in 1943 drew attention to this method of treatment but do not seem to have influenced other surgeons as much as they deserved. Berkman and Miles described its use in twenty cases of simple metacarpal fractures and claimed that angulation, shortening and over-riding can be controlled by this method. They left lhe K-wire projecting ¼in. out of the skin and sealed it off with collodion and recommended the insertion of the wire while the hand was clenched into a fist. Two wires were used for mid-shaft fractures and one for neck or base. Waugh and Ferrazzano (1943) described twenty-two cases of metacarpal fractures which they had treated in this way and were pleased with the results. The wire was introduced The H a n d - - V o L 5

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Unstable Fractures of the Metacarpals--Douglas W. Lamb, Peter A. Abernethy, Peter A. M. Raine

under local anaesthesia and was left projecting, being incorporated in a light plaster including wrist and hand but allowing for finger movement. The wires were left in three weeks. This method of treatment has been utilised in our centre when internal fixation was considered necessary for the past fourteen years. SUMMARY

Sixty-six cases of unstable metacarpal fractures treated by percutaneous~ insertion of transverse K-wires to adjacent intact metacarpals have been reviewed. The technique is simple and effective and worthy of a wider appreciation of its merits. It is recommended that where possible at least one K-wire should be introduced into each side of the fracture and that the power drill should be used. No serious complication of the technique has occurred in the cases reviewed. In particular there has been no case of delayed or non-union. The functional results were excellent. There appeared to be a much higher incidence of persistent pain and weakness where there had been incomplete correction of deformity at the fracture site.

REFERENCES

BERKMAN, E. F. and MILES, G. H. (1943) Internal Fixation of Metacarpal FracturesExclusive of the Thumb. Journal of Bone and Joint Surgery. 25; 816-821. BUNNELL'S Surgery of the Hand (1970--5th edition) Edited by Joseph H. Boyes. Philadelphia. J. B. Lippincott Company. 601. HOWAROD, L. D. Fractures of the Small Bones of the Hand. Instructional Course Booklet. FURLONG, R. (1957) Injuries of the Hand. J. and A. Churchill Ltd. MILFORD, L. (1971) The Hand (Campbells Operative Orthopaedics) (1971) St. Louis. C. V_ Mosby Company. THE HAND (1966) Clinical Surgery. Edited by R. G. Pulvertaft. Butterworths. JAMES, J. I. P. (1966) Fractures of the Phalanges and Metacarpals. Proc. British Club for Surgery of the Hand, London. VOM SAAL, F. H. (1953) Intramedullary Fixation in Fractures of the Hand and Fingers.. Journal of Bone and Joint Surgery. 35-A, 5-16. WAUGH, R. L. and FERRAZZANO, G. P. (1943) Fractures of the Metacarpals Exclusiveof the Thumb. A New Method of Treatment. American Journal of Surgery. 59: 186-194. 48

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