Type II D Phalangeal Neck Fractures in Children: A Series of 20 Cases Treated According to a Preset Stepwise Algorithm

Abstract

Introduction Type II phalangeal neck fractures are defined as displaced fractures with bone-to-bone contact at the fracture site. In the type II D subtype, the distal fracture fragment is thin. A review of the literature did not reveal any study investigating the outcome of management of these fractures.

Patients and Methods This is a retrospective study of 20 consecutive children with type II D phalangeal neck fractures treated over the past 4 years. Demographic data were reviewed. All cases were managed according to the preset stepwise algorithm. The outcome of management at final follow-up was documented using Al-Qattan’s grading system.

Results The mean age was 30 months (range 12–80 months). There were 12 males and 8 females. The mean follow-up was 2 years (range 7 months to 3 years). The largest two categories within the management algorithm were patients with minimally displaced fractures treated conservatively ( n = 8) and those with displaced fractures treated with closed reduction and percutaneous K-wire fixation ( n = 9). Fischer exact test was used to compare the outcome in these two groups and the p value was significant ( p = 0.015), indicating a significantly better outcome in the former group.

Conclusion Several conclusions were made from the study. Type II D of phalangeal neck fractures tend to occur in young children and the majority involve the middle phalanx. The thinness of the distal fracture fragment makes standard techniques of closed reduction more difficult. However, flexion of the proximal and distal joints appears to be effective in reducing dorsally displaced type II D fractures by closed means. Finally, a more conservative approach to minimally displaced type II D fractures results in a better outcome compared with closed reduction and percutaneous K-wire fixation.

Introduction

Phalangeal neck fractures in children are labeled as “problematic” 1 and carry a high risk of complications such as malunion, nonunion, resorption, avascular necrosis, and stiffness. 2

Phalangeal neck fractures are classified into three types: non displaced (type I), displaced with bone-to-bone contact at the fracture site (type II), and displaced with no bone-to-bone contact (type III). 3 Type II fracture are the most common and they have been recently subclassified into 4 subtypes 4 as shown in Fig. 1 . The classic type II A fracture has a transverse fracture line at the neck of the phalanx. In type II B fractures, the oblique fracture line allows the surgeon to use oblique (instead of axial) K-wires; hence, fixation is relatively easier and avoids joints. Type II C fractures have a dorsal flange. The flange gives the fracture relative stability and fixation can be done through the flange. Type II D fractures have a thin distal fracture fragment and are considered to be the most challenging because the thin fragment is more difficult to reduce by closed means. Furthermore, type II D fractures carry a high risk of iatrogenic comminution of the distal fracture fragment during manipulation and K-wire fixation. 4 A review of the literature did not reveal any study investigating the outcome of management of type II D fractures.

Fig. 1.

The 4 sub-types of type II phalangeal neck fractures.

In this article, we present a case series of 20 children with type II D phalangeal neck fractures treated according to a preset stepwise algorithm and document the outcome of their management.

Patients and Methods

This is a retrospective study of 20 consecutive children with type II D phalangeal neck fractures treated by the senior author (MMA) over the past 4 years. The study only included children who had a minimum of 6 months of follow-up. Demographic data (age, sex, fracture site) were reviewed. All cases were managed according to the preset stepwise algorithm shown in Fig. 2 . In the algorithm, minimally displaced fractures are those in which the bone-to-bone contact between the proximal and distal fragments is equal or greater than 75% as per the lateral radiographic view. If the contact is less than 75%, the fracture is considered as significantly displaced ( Fig. 2 ). The outcome of management at final follow-up was documented using Al-Qattan’s grading system 5 shown in Table 1 .

Fig. 2.

The stepwise algorithm for treating type II D fractures used in the current study. The algorithm also shows the number of cases in each category along the algorithm.

Table 1. Al-Qattan’s grading system for classification of the outcome of management of phalangeal neck fractures in children.

Outcome	Union of the fracture	Range of motion	Residual deformity	Digit function
Abbreviations: DIPJ, distal interphalangeal joint of the fingers; IPJ, interphalangeal joint at thumb; PIPJ, proximal interphalangeal joint of the fingers.
Excellent	Yes	Full (compared with the contralateral hand)	No	Normal
Good	Yes	Greater than 50°at the IPJ/DIPJ Greater than 90°at the PIPJ	No	Good
Fair	Yes	10°–50°at the IPJ/DIPJ 50°–90°at the PIPJ	Mild	Useful
Poor	No	Less than 10°at the IPJ/DIPJ Less than 50°at the PIPJ	Severe	Lost (amputation) or significant loss of function

Results

The study included 20 children. The mean age was 30 months (range 12–80 months). There were 12 males and 8 females. The proximal phalanx of the thumb was fractured in 2 cases. In the fingers, the fractures were located at the neck of the middle phalanx in 17 cases and at the neck of the proximal phalanx in one case.

The number of cases in each category along the management algorithm is shown in Fig. 2 and the outcome at a mean follow-up of 2 years (range 7 months to 3 years) is shown in Table 2 . The largest two categories were patients with minimally displaced fractures treated conservatively ( n = 8) and those with displaced fractures treated with closed reduction and percutaneous K-wire fixation ( n = 9). Fischer exact test was used to compare the outcome in these two groups and the p value was significant ( p = 0.015); indicating a significantly better outcome in the former group.

Table 2. The final outcome in the current study groups of 20 cases.

Category (as per the algorithm shown in Fig. 2 )	Outcome (as per the criteria shown in Table 1 )
	Excellent	Good	Fair	Poor
Concurrent ischemia (1 case)	–	–	–	1
Minimally displaced fractures treated conservatively (8 cases)	7	1	–	–
Displaced fractures treated with closed reduction and percutaneous K-wire fixation (9 cases)	2	7	–	–
Displaced fractures requiring open reduction and K-wire fixation (one case)	–	–	–	1
Late presentation with malunion treated conservatively (one case)	–	1	–	–

One case presented with an open fracture and concurrent ischemia of the fractured thumb ( Fig. 3 ). The skin was sutured and no fracture fixation was attempted. The digit survived but the fracture did not unite. Instead, there was gradual resorption of the distal fracture fragment and the final outcome was poor. The outcome was considered poor not only because of the nonunion (secondary to resorption of the distal fragment), but also because of the fixed flexion deformity of the interphalangeal joint ( Table 1 ). This flexion deformity was possibly secondary to disruption of the extensor tendon and subluxation of the joint. In retrospect, splinting of the joint in full extension for 6 weeks after injury might have reduced the degree of flexion deformity. Functionally, the family reported that the child was using the injured thumb well in all daily activities.

Fig. 3.

The case with concurrent ischemia at the time of the injury. No attempt was done for fixation of the open fracture. ( A ) X-ray at the time of injury showing the fracture and the adjacent injury to the base of the distal phalanx. ( B ) X-ray at 3 months showing the nonunion and the partial resorption of the distal fracture fragment. ( C ) X-ray at 8 months showing the complete resorption of the distal fracture fragment and the sclerosis of the fracture line of the proximal fragment. ( D ) Clinically, there is fixed flexion contracture of the interphalangeal joint of the thumb and the outcome is poor.

Eight cases presented early with minimally displaced fractures and no concurrent ischemia. All cases were treated conservatively with an above-elbow cast for 4–5 weeks; and casts were changed weekly to check for fracture displacement radiologically. All children had radiograghic and clinical assessment at final follow-up. All fractures united with no residual deformity. The outcome was considered excellent (with full range of motion) in seven cases and good in the remaining case because of 20° loss of range of motion at the distal interphalangeal joint in the arc of flexion. The presence of mild flattening of the phalangeal head was not associated with the loss of range of motion ( Fig. 4 ).

Fig. 4.

A minimally displaced fracture managed conservatively ( A ) X-ray at the time of injury; ( B ) X-ray at 8 weeks. There is no tenderness at the fracture site but the fracture line is still visible. ( C ) X-ray at 2 years. There is union with mild phalangeal head deformity. There was full range of motion at the distal interphalangeal joint and the outcome was excellent.

Ten cases (nine dorsally displaced fractures and one volarly displaced fracture) presented early with significantly displaced fractures requiring a trial of closed reduction. Closed reduction was done under general anesthesia in the operating room under X-ray control. Flexion of the proximal and distal joints resulted in adequate reduction in all of the nine dorsally displaced fractures ( Fig. 5 ). All reductions were unstable since fractures redisplaced dorsally once the joints were extended. Hence, percutaneous K-wire fixation was done in these nine cases with the joints in flexion using the techniques shown in Fig. 5 . The limb was immobilized in an above-elbow cast until the time of K-wire removal in 4 to 5 weeks. The final outcome was excellent in two and good in seven cases. The tenth case in this group had a volarly displaced fracture and the “joint flexion” technique failed to result in an adequate reduction. Open reduction and K-wire fixation (for 5 weeks) was done in this case but the outcome was poor because of avascular necrosis ( Fig. 6 ).

Fig. 5.

Closed reduction and percutaneous K-wire fixation with a good outcome. ( A ) The displaced fracture. ( B ) Flexion of the proximal and distal joints not only reduces the fracture, but also maintains the reduction. The K-wire is then inserted into the center of the phalangeal head and through the diaphysis across the flexed PIP joint. ( C ) Appearance of the finger with the K-wire in place. The wire is then withdrawn until the DIP joint is free and is then pushed back across the extended DIP joint until the PIP joint is free. ( D ) The final appearance of the wire. ( E ) The healed fracture at 6 months. The outcome was good.

Fig. 6.

Avascular necrosis following open reduction and K-wire fixation. ( A ) The fracture is volarly displaced and closed reduction failed. ( B ) The K-wire is inserted after open reduction. ( C ) X-ray at 8 weeks (3 weeks post removal of the K-wire). The fracture line is still visible. ( D ) X-ray at 8 months showing avascular necrosis.

Finally, one child presented two months after injury with malunion. The fracture was treated conservatively and showed remodeling; resulting in a good outcome ( Fig. 7 ).

Fig. 7.

A child with a malunited fracture treated conservatively. ( A ) Clinical appearance of the injured digit at 2 months after injury (at the time of presentation to the author). Note the dorsal swelling. ( B ) X-ray at 2 months after injury showing early union between the center of the phalangeal head and the dorsal cortex of the diaphysis. Also note the periosteal reaction on the dorsal aspect of the diaphysis. ( C ) X-ray at 6 months showing some remodeling (d) X-ray at 1 year showing further remodeling and union ( E ) and ( F ) clinical outcome at 1 year. There is no more dorsal bulge and range of motion of the DIP joint is 60°. The outcome is good.

Discussion

The current study investigated the outcome of type II D phalangeal neck fractures in children according to a preset algorithm of management. The mean age of 30 months indicated that type II D fractures tend to occur in young children. As shown in Table 2 , two cases (10%) had a poor outcome. In one case, there was a concurrent ischemia of the digit and this is known to be a poor prognostic factor affecting the outcome of phalangeal neck fractures. 5 6 The other case with a poor outcome was the only fracture that required open reduction and K-wire fixation. It is now well established that open reduction is a risk factor for avascular necrosis of the phalangeal head. Topouchian et al 7 reported on 13 cases treated with open reduction and K-wire fixation and 4 cases (31%) showed evidence of avascular necrosis. Hence, most authors recommend attempting closed or percutaneous reduction prior to proceeding to open reduction of phalangeal neck fractures. 8 9 There are other factors that increase the risk of avascular necrosis including the multiple K-wire passes through the phalangeal head, and the iatrogenic comminution of the phalangeal head. In our case with avascular necrosis, these were not contributing factors. In fact, the X-ray at 8 weeks (3 weeks after removal of the K-wire) showed an acceptable reduction without comminution ( Fig. 6C ). This indicated that the avascular necrosis was only secondary to ischemia of the phalangeal head. Knowing the risk of avascular necrosis with open reduction, one might also argue that failure of closed reduction is an absolute indication for a trial of conservative management as long as there is some bone-to-bone contact between the two fracture fragments (in our case there was 50% contact as seen in Fig. 6A ).

The largest two groups of patients in the current study were children with minimally displaced fractures treated conservatively ( n = 8) and those who had displaced fractures treated with closed reduction and percutaneous K-wire fixation ( n = 9). Although the outcome was generally satisfactory in all 17 cases, the outcome was significantly better in the former group. This may be related to the degree of severity of the original injury (which is expected to correlate with the degree of displacement) or may be related to the trauma induced by the K-wire in the latter group. In his original article, Al-Qattan 3 recommended K-wire fixation for all type II fractures. More recently, most centers (including ours) have adopted a more conservative approach to minimally displaced fractures as long as there is no rotational deformity. 8 10 Our results support the conservative approach in minimally displaced type II D fractures.

Our series also included one case of malunion treated conservatively. There was significant remodeling resulting in a good outcome ( Fig. 7 ). Remodeling of malunited type IIA fractures was reported by several authors 11 12 13 14 ; our series demonstrates remodeling in a type II D fracture. This remodeling capacity of malunited phalangeal neck fractures is interesting since the facture line is far from the growth plate. It also raises the argument of what the limit is of the degree of displacement that may be allowed to have a trial of conservative management: Is it the 75% of contact recommended in the current study or is 25% of contact acceptable? Further studies are mandatory to investigate this point; with long term follow-up since complete remodeling after malunion of these fractures may take over 18 months. 11 12 13 14

Closed reduction of phalangeal neck fractures should be done in the operating room under X-ray control to avoid iatrogenic comminution of the phalangeal head. 15 For type II A fractures, several techniques of closed reduction have been described 4 such as applying gentle manual pressure over the dorsally displaced phalangeal head and the use of a K-wire as a “lever” or “joystick” to reduce the dorsally displaced fracture. The latter technique was inspired by the Kapandji technique for dorsally displaced distal radius fractures. 16 17 We believe that such techniques are difficult to apply to the thin distal fracture fragment of type II D fractures; we document that flexion of the proximal and distal joints is effective in reducing type II D fractures by closed means.

Another interesting finding in the current study is the fact that the majority of type II D fractures were located in the middle phalanx. Hence, we were unable to compare fractures of the middle versus the proximal phalanx. Furthermore, the placement of K-wires varies according to the site of the fracture: fractures of the middle phalanx are usually fixed with K-wires crossing the interphalangeal joint, 4 while those of the proximal phalanx are best fixed with K-wires avoiding all joints as previously described. 18

Weaknesses of the current study include the retrospective nature of the study, the relatively small study group, and the relatively short follow-up in some cases since a minimum of 6 months of follow-up was one of the inclusion criteria. However, it is well established in the literature 4 that all complications of phalangeal neck fractures (such as malunion, nonunion, avascular necrosis, and stiffness) are evident within 6 months. The only exception is remodeling of malunited factures which may take up to 18 months as we previously discussed.

The current study has several strengths including the inclusion of a very specific group of children with type II phalangeal neck fractures, the use of preset algorithm of management, and management being done by a single experienced surgeon.

Several conclusions may still be made from the current study. Type II D of phalangeal neck fractures tend to occur in young children and the majority involve the middle phalanx. The thinness of the distal fracture fragment makes standard techniques of closed reduction more difficult. However, flexion of the proximal and distal joints appears to be effective in reducing dorsally displaced type II D fractures by closed means. Finally, a more conservative approach to minimally displaced type II D fractures appears to be adequate and results in a better outcome compared with closed reduction and percutaneous K-wire fixation. Our study also calls for an investigation of the conservative management of phalangeal neck fractures with lesser degrees of bone-to-bone contact between the proximal and distal fracture fragments. This more conservative approach should be considered especially in cases with failed closed reduction, knowing the significant risk of avascular necrosis following open reduction and K-wire fixation of these fractures. 7

Funding Statement

Funding The work was supported by the College of Medicine Research Center, Deanship of Scientific Research, King Saud University, Riyadh, Saudi Arabia.