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A Comparative Study of Clinical and Radiological Outcomes of Dorsally Angulated, Unstable Distal Radius Fractures in Elderly Patients: Intrafocal Pinning Versus Volar Locking Plating
A Comparative Study of Clinical and Radiological Outcomes of Dorsally Angulated, Unstable Distal Radius Fractures in Elderly Patients: Intrafocal Pinning Versus Volar Locking Plating Toshihisa Oshige, MD, Akinori Sakai, MD, PhD, Yukichi Zenke, MD, Shiro Moritani, MD, Toshitaka Nakamura, MD, PhD From the Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan; Department of Orthopaedic Surgery, Kagawa Rosai Hospital, Marugame, Japan.
Purpose: To compare the clinical and radiological outcomes of intrafocal pinning (IFP) and volar locking plating (VLP) of dorsally angulated, unstable distal radius fractures in elderly patients. Methods: The subjects were 62 consecutive patients over 60 years of age with dorsally angulated, unstable distal radius fractures treated with IFP or VLP. Bone mineral density (BMD) of the lumbar spine was measured by dual-energy x-ray absorptiometry at first examination. The range of motion and grip strength were measured at follow-up examinations, and ulnar variance (UV) was measured on radiographs at baseline and follow-up postoperative examinations. Results: There were no notable differences in gender, age, follow-up period, baseline UV, BMD, and AO classification between IFP and VLP groups. There was no difference between the UV in VLP immediately after surgery and at the final follow-up examination; however, IFP showed a significant loss of reduction as measured by UV. In patients with UV more than 5 mm or BMD less than 70% of young adult mean (YAM) at first examination, UV increased again at the final follow-up examination in IFP, while surgically corrected UV was maintained in VLP, independent of the degree of baseline UV and BMD. VLP resulted in earlier recovery of postoperative range of motion and grip strength compared with IFP. The range of flexion and the grip strength value were significantly larger in VLP at final examination. Conclusions: VLP, but not IFP, can maintain surgically corrected UV in distal radius fractures, independent of the degrees of initial UV and BMD. VLP enhances earlier recovery in range of motion and grip strength than IFP. (J Hand Surg 2007;32A:1385–1392. Copyright © 2007 by the American Society for Surgery of the Hand.) Type of study/level of evidence: Therapeutic II. Key words: Radius fracture, intrafocal pinning, volar locking plate, ulnar variance, osteoporosis.
istal radius fractures are common in the elderly, and at least some benefit from internal fixation. Various surgical techniques are used for the treatment of dorsally displaced, unstable distal radius fractures, such as percutaneous pinning,1,2 intramedullary pinning3,4 or nail,5,6 external fixation,7,8 and internal fixation with various plates.9,10 There is no standardized protocol,
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however, for the management of these fractures.11 Thus, there is a need for objective comparisons of the various treatment alternatives for the surgical treatment of these fractures. The ideal surgical method should maintain anatomical position and ensure early mobilization. Anatomical reduction with stable fixation is the preferable treatment of unstable distal radius fractures.
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Percutaneous pinning techniques with or without external fixation are historically the most popular. Recent studies, however, described the usefulness of volar locking screw/plate implants, which can stabilize cancellous, fragmented bone for the treatment of dorsally displaced, unstable distal radius fractures in elderly patients.9,12 The differences in outcomes between percutaneous pinning and volar locking plating are not well reported, so we present postoperative data on serial radiological changes and functional recovery comparing these two methods. Elderly patients with distal radius fractures frequently have low bone mineral density (BMD). Low BMD in women is a risk factor for low-energy Colles’ fractures.13 More than half of elderly women with a distal radial fracture have osteoporotic BMD values for the lumbar spine or hip.14 Osteoporosis is characterized by the presence of both low BMD and disruption of normal bone architecture that leads to bone fragility. In Japan, osteoporosis is diagnosed when BMD falls below 70% of the young adult mean (YAM) (age 20 – 44 years).15 This diagnostic criterion is equivalent to that proposed by the World Health Organization, which defines osteoporosis as a BMD value ⬍2.5 SD of YAM (age 20 – 40 years).16 The subjects of this study included patients with and without osteoporosis. Our study investigated whether the degree of bone fragility as measured by BMD should be a factor in selecting the surgical procedure for distal radius fractures. We prospectively and consecutively treated elderly patients with dorsally angulated, unstable distal radius fractures using intrafocal pinning (IFP) (Kapandji’s method1) from 2002 to 2003 and volar locking plating (VLP) in 2004. The plate used in this study was the distal radius volar locking plate system (DRV2, Mizuho Co., Tokyo, Japan) developed by Osada et al.17,18 In this study, we compared the clinical and radiological outcomes of the two treatment modalities of IFP and VLP.
Materials and Methods Subjects All patients with distal radius fractures were initially managed with closed reduction and splinting, and patients with unstable or unsuccessful reduced fractures underwent surgery. The indications for internal fixation included dorsal angulation ⬎10°, radial inclination angle ⬍15°, or ulnar variance (UV) ⬎3 mm. Osteoporosis was not a criterion for inclusion into the study. The enrolled subjects were 62 consecutive patients over 60 years of age with 62 dor-
sally angulated, unstable distal radius fractures treated with IFP for 31 patients and VLP for 31 patients from 2002 to 2004 at our institution. We prospectively treated consecutive patients with IFP from 2002 to 2003 and VLP in 2004. All patients consented to the study participation at the first visit, and all aspects of the study were approved by the institutional review board. We observed that the final UV value in IFP was approximately 2.5 mm and that in VLP was approximately 0.5 mm based on our clinical experience before starting the present study. To determine the number of patients required for meaningful statistical analysis, we performed power analysis before the conduct of the study.19 We used 2.0 as the minimum difference we wished to detect as significant, assuming ␣⫽0.05 (two-sided) and ⫽0.2 (power⫽80%). The analysis identified 25 as the minimum number of subjects required for each group. Subjects of the IFP group were 2 men and 29 women, and the VLP group comprised 5 men and 26 women (Table 1). The mean age of the patients at the time of surgery was 71 years (range, 60 – 87) for the IFP group, and 70 years (range, 60 –94) for the VLP group. All patients were followed up regularly with physical and radiological examinations for at least 6 months after surgery. The mean period of follow-up was 13 months (range, 6 –30) for the IFP group and 11 months (range, 6 –23) for the VLP group. UV on baseline radiographs after injury was ⬎5 mm in 7 patients and ⱕ5 mm in 24 patients of the IFP group, and 11 and 20 patients of the VLP group, respectively. There were no notable differences in gender, age, follow-up period, or baseline UV between IFP and VLP groups. BMD of the lumbar spine (L2-L4) was measured by dual-energy x-ray absorptiometry (QDR-4500, Hologic Inc., Bedford, MA) at the first visit. In the IFP group, the BMD/YAM ratio was ⱖ80% in 9 patients, 70 – 80% in 14 patients, and ⬍70% in 8 patients. In the VLP group, the corresponding numbers of patients were 8, 16, and 7. According to the AO classification scheme),20 25 fractures were considered type A (extra-articular fractures involving neither the radiocarpal nor the radioulnar joint) fractures (3 A2 and 22 A3) and 6 type C (complex articular fractures affecting the joint surface and metaphyseal area) fractures (5 C1 and 1 C2) for the IFP group, and 27 type A fractures (7 A2 and 20 A3) and 4 type C fractures (3 C1 and 1 C2) for the VLP group. Articular fractures were identified in 6 patients of the IFP group and 4 patients of the VLP
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Table 1. Patient Characteristics Number of cases Gender (male:female) Age (years) Follow-up period (months) UV (number of cases) ⬎ 5 mm ⱕ 5 mm BMD (number of cases) ⬍ 70% of YAM ⱖ 70% of YAM AO classification type (number of cases) A C
IFP
VLP
p Value
31 2 : 29 70.7 (60–87) 13 (6–30)
31 5 : 26 69.9 (60–94) 11 (6–23)
NS NS NS
7 24
11 20
NS
8 23
7 24
NS
25 6
27 4
NS
The p value was determined by Mann-Whitney U test for age and follow-up period and by chi-square test for gender, baseline UV, BMD, and AO classification type. Values of age and follow-up period represent the mean and (range). NS: not significant.
group. The intra-articular step-off of these patients, however, was not greater than 2 mm. There were no notable differences in BMD and the AO classification between the IFP and VLP groups. Surgical Treatment Surgery was performed under a brachial plexus block anesthetic. IFP was based on the procedure described by Kapandji.1 We inserted three K-wires (1.8-mm [0.071-in.] diameter) into the fracture site of the radius with fracture reduction. One was inserted into the proximal portion of Lister’s tubercle and another between the tendons of the extensor digitorum communis. These 2 wires were placed dorsal to volar. The other wire was inserted between the tendons of the extensor pollicis brevis and extensor carpi radialis longus. This wire was placed radial to ulnar, entering at the radial styloid. The mean duration of surgery was 22 minutes. A below-elbow plaster cast was applied for 3 weeks after surgery. The K-wires were removed 6 weeks after surgery. Active finger motion was encouraged early after surgery, and forearm rotation was initiated within 4 to 5 days after surgery. Active and active-assisted motion of the wrist joint was started to patient tolerance after the plaster cast was removed. Passive exercises were started 6 weeks after surgery and continued until 12 weeks after surgery. VLP was performed with a longitudinal skin incision along the tendon of the flexor carpi radialis from the distal palmer wrist crease to approximately 6 cm proximally. The sheath of the flexor carpi radialis tendon was incised, and the tendon and flexor pollicis longus muscle were retracted ulnarly. The radial bor-
der of the pronator quadratus muscle was cut longitudinally. The volar aspect of the radius was exposed subperiosteally. A volar locking plate was placed directly on the radius after fracture reduction. A plate used in this study was the distal radius volar locking plate system (DRV2, Mizuho Co., Tokyo).17,18 No bone grafting was used. After fixation, the pronator quadratus was repaired over the plate with absorbable suture. The mean duration of surgery was 50 minutes. No plaster cast was applied after surgery. A removable wrist brace was used for support between exercises for 3 weeks after surgery. Active finger motion was encouraged early after surgery. Forearm rotation and active and active-assisted motion of the wrist joint were started within 4 –5 days after surgery to patient tolerance. Passive exercises started 6 weeks after surgery and continued until 12 weeks after surgery. Outcome Evaluations The degree of fracture displacement was assessed by measuring UV, radial inclination angle, and dorsal angulation, based on standard anteroposterior and lateral projection radiographs taken on the basis of the quality criteria described by Metz and Gilula21 and Goldfarb et al22 at the first visit, immediately after surgery, and at the final visit. In addition, we checked the wrist and forearm range of motion (extension, flexion, pronation, and supination) and grip strength at 3, 4, 6, 8, and 12 weeks and at final examination after surgery for the IFP group and at 1 and 2 weeks as well as after surgery for the VLP group.
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Analysis of the Radiological Data After Dividing Patients into Subgroups We analyzed the radiological data of UV, radial inclination angle, and dorsal angulation by dividing patients into subgroups, respectively, when there were notable differences in the respective final radiological outcomes between IFP and VLP groups. We divided patients into two subgroups based on the degree of baseline UV and BMD at first examination. First, the subgroups were baseline UV ⬎5 mm and baseline UV ⱕ5 mm. Second, the subgroups were BMD ⱖ70% of YAM and BMD ⬍70% of YAM. Preoperative Factors That Could Contribute to the Final Radiological Outcomes We investigated the preoperative factors that could influence the final outcome when there were notable differences in the respective final radiological outcomes between IFP and VLP groups. The candidate preoperative factors were age, baseline UV, BMD, and the AO classification of the fractures. Statistical Analysis Results were expressed as mean ⫾ standard error of the mean (SEM). Differences between IFP and VLP were evaluated using the Mann-Whitney U test for age, follow-up period, and UV values at each time point, and using the chi-square test for gender, baseline UV, BMD, and AO classification type. Differences in UV values immediately after surgery and at the final follow-up examination were evaluated using paired Student’s t-test. The significant preoperative factors for final UV in IFP were determined by logistic regression analysis. A p value of ⬍0.05 was considered significant. Statistical analysis was performed using StatView 5.0 software (SAS Institute, Cary, NC).
Results General Results and Complications Sound union occurred in all cases. Rupture of the tendon of extensor pollicis longus occurred in 2 cases of the IFP group and 1 case of the VLP group. The cause of this rupture following the use of a volar plate was not elucidated. Pin track superficial infection at the sites of K-wire insertion occurred in 4 cases of the IFP group, but all cases showed excellent healing after removal of the wires. None of the patients developed deep infection or complex regional pain syndrome.
UV (mm) 6 IFP 4
VLP
++
2
*
0 -2 initial
immediately after surgery
final
Figure 1. Changes in UV. Data are mean ⫾ SEM. *p⬍0.05 vs. IFP by Mann-Whitney U test. ⫹⫹p⬍0.01 vs. immediately after surgery in each group by paired Student’s t-test.
Radiological Findings For the IFP group, the mean degree of radial inclination was 24° immediately after surgery and 22° at the final follow-up examination. The respective values for the VLP group were 22° and 22°. The change in radial inclination was not statistically different between the two groups. The mean degree of dorsal angulation was 6° immediately after surgery and 4° at the final follow-up examination for the IFP group, and 8° and 4° for the VLP group, respectively. There was no difference in dorsal angulation between the two groups. The mean UV was 0 mm immediately after surgery and 2 mm at the final follow-up examination for the IFP group and was 0 mm and 1 mm for the VLP group (Fig. 1). There were no differences between the UV in VLP immediately after surgery and at the final follow-up examination; however, IFP showed a significant loss of reduction (p⬍0.01), as measured by UV. Analysis of the Radiological Data After Dividing Patients into Subgroups There was a significant difference (p⬍0.05) in the final UV between IFP and VLP groups. Thus, we analyzed the UV data by dividing patients into two subgroups. For the IFP subgroup with baseline UVⱕ5 mm (UVⱕ5-IFP group), the mean length of UV was 2 mm at injury, 1 mm immediately after surgery, and 1 mm at the final follow-up examination, compared with 7 mm, 1 mm, and 4 mm, respectively, for the UV⬎5-IFP group (Fig. 2A). The UV value determined at the final follow-up examination was significantly higher (p⬍0.01) in the UV⬎5-IFP group than that of the UVⱕ5-IFP group. For the VLP subgroup with baseline UVⱕ5 mm (UVⱕ5-VLP group), the mean length of UV was 2 mm at injury, 0 mm immediately after surgery, and 1 mm at the final
Oshige et al / Pinning Versus Plating for Distal Radius Fractures UV (mm)
UV (mm) 12
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immediately after surgery
final
initial
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final
Figure 2. Changes in UV in patients with baseline UV ⬎5 mm or ⱕ5 mm. (A) IFP. (B) VLP. Data are mean ⫾ SEM. **p⬍0.01 vs. subgroup with UVⱕ5 mm in each group, #p ⬍0.05, ##p ⬍0.01 vs. respective subgroups of IFP by Mann-Whitney U test. ⫹p ⬍0.05, ⫹⫹p⬍0.01 vs. immediately after surgery of respective subgroups in each group by paired student’s t-test.
Preoperative Factors That Could Contribute to the Final Radiological Outcomes There was a significant difference (p⬍0.05) in the final UV between IFP and VLP groups. The final UV was not adequately maintained in certain subgroups of the IFP group, while VLP maintained the surgically corrected UV, independent of the degree of baseline UV and BMD. The preoperative factors that significantly contributed to the final UV in the IFP group were baseline UV⬎5 mm and BMD⬍70% of YAM (Table 2). The relative risk was 2.90 (95% confidence interval [CI]: 1.39 – 6.06) in cases with baseline UV⬎5 mm and 1.59 (95% CI: 1.02 – 2.47) in cases with BMD⬍70% of YAM. Age and AO classification of the fractures were not notable independent factors that aggravated the final UV in the IFP group. There was no relationship between BMD and AO classification.
follow-up examination, compared with 8 mm, 0 mm, and 1 mm, respectively, for the UV⬎5-VLP group (Fig. 2B). The final UV values were not different between the two VLP subgroups. The final UV values of the VLP group were significantly lower than those of the IFP group for both the UVⱕ5 mm and UV⬎5 mm subgroups. For the IFP group, the mean length of UV of the subgroup with BMDⱖ70% of YAM at first examination (ⱖ70% BMD-IFP group) was 2.7 mm at injury, 0.2 mm immediately after surgery, and 2 mm at the final follow-up examination, and 4 mm, 1 mm, and 3 mm, respectively, in the ⬍70% BMD-IFP group (Fig. 3A). On the other hand, for the VLP group, the mean length of UV was 3 mm at injury, 0 mm immediately after surgery, and 1 mm at the final follow-up examination in the ⱖ70% BMD-VLP group, and 5 mm, 0 mm, and 1 mm, respectively, in the ⬍70% BMD-VLP group (Fig. 3B). The final UV values were not different between the two VLP subgroups, while those of the VLP group were significantly lower (p⬍0.05) than the IFP group for both BMD ⱖ70% and ⬍70% of YAM.
Range of Motion VLP resulted in earlier recovery of postoperative range of motion, including extension (Fig. 4A) and flexion (Fig. 4B) of the wrist joint and pronation (Fig.
UV (mm)
UV (mm) 10
10 BMD 㸱 70% of YAM
8
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8
BMD Ӎ 70% of YAM
6 4 2
#
0
#
-2 initial
immediately after surgery
final
B
initial
immediately after surgery
final
Figure 3. Changes in UV in patients with BMD ⬍70% of YAM or ⱖ70% of YAM. (A) IFP. (B) VLP. Data are mean ⫾ SEM. *p ⬍0.05 vs. subgroup of BMDⱖ70% of YAM in each group, #p ⬍0.05 vs. respective subgroups of IFP by Mann-Whitney U test. ⫹p ⬍0.05, ⫹⫹p ⬍0.01 vs. immediately after surgery of respective subgroups in each group by paired student’s t-test.
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Table 2. Preoperative Factors That Aggravated the Final UV in IFP Preoperative Factors UV at the initial radiographs ⬎ 5 mm BMD at the initial examination ⬍ 70% of YAM
p Value
Relative Risk
95% CI
⬍0.01
2.90
1.39-6.06
⬍0.05
1.59
1.02-2.47
The p value, relative risk, and 95% CI were determined by logistic regression analysis. CI, confidence interval.
and grip strength compared with IFP. Because there are many surgical procedures but no strict guidelines for treatment of dorsally angulated, unstable distal radius fractures and no selection criteria for surgery, treatment depends on the surgeons’ choice. Under these circumstances, our study provides new data that VLP is superior in maintaining earlier postoperative reduction compared with IFP in elderly patients with initial radial shortening and UVⱖ5 mm or osteoporosis with BMD⬍70% of YAM at first examination. The ability of IFP to maintain postoperative reduction is poorer than VLP.2,10 There is no information on the importance of BMD on maintenance of earlier postoperative reduction by surgery for distal radius fractures, although it is reported that the BMD in the contralateral distal radius is an important prognostic parameter of possible deformity of the radius after closed reduction and casting.23 In elderly patients, bone strength decreases in proportion with reduction
4C) and supination (Fig. 4D) of the forearm, compared with IFP. The degree of flexion was significantly larger (p⬍0.01) in the VLP group than in the IFP group at the final examination. Grip Strength VLP resulted in earlier recovery of grip strength after surgery compared with IFP (Fig. 5). Recovery to the 50% level of the opposite uninjured side was achieved in approximately 3 weeks in the VLP group and in approximately 12 weeks in the IFP group. The grip strength of the VLP group was significantly larger (p⬍0.01) than that of the IFP group at the final examination. Discussion The present study demonstrated that in elderly patients, VLP, but not IFP, could maintain postoperative reduction, independent of the degree of UV and BMD at baseline, and that VLP was associated with early postoperative recovery of the range of motion
Degree of extension (% of the opposite uninjured side) 100 㸟㸟
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Figure 4. Serial postoperative changes in range of motion. (A) Extension. (B) Flexion. (C) Pronation. (D) Supination. Data are mean ⫾ SEM. *p ⬍0.05, **p ⬍0.01 vs. IFP by Mann-Whitney U test.
Oshige et al / Pinning Versus Plating for Distal Radius Fractures Grip strength (% of the opposite uninjured side) 100 IFP
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Figure 5. Serial postoperative changes of grip strength. Data are mean ⫾ SEM. **p ⬍0.01 vs. IFP by Mann-Whitney U test.
in BMD, and fractures of the distal radius, an osteoporotic fracture, frequently occurs. BMD is a major determinant of bone strength. The radius seems to be fractured with more severe displacement and shortening in osteoporotic patients than in nonosteoporotic patients, even when the same force is applied to the bone. In this study, the baseline UV value at injury was 5 ⫾ 1 mm in patients with BMD⬍70% of YAM and 3 ⫾ 0 mm in patients with BMDⱖ70% of YAM. Thus, the baseline UV value of patients with osteoporosis was significantly larger (p⬍0.05) than that of patients without osteoporosis. It seems reasonable to select surgical procedures based on the level of fracture displacement and the BMD of the patient. VLP is a reliable plating system for the fixation of unstable distal radius fractures. Previous studies examined biomechanical changes in distal radius fractures stabilized by VLP. Drobetz et al24 reported that the subchondral plate-screw-bone constructs of VLP systems showed significantly greater rigidity, indicating higher resistance to postoperative loads and displacement force, and resulted in the maintenance of radial length after surgery. Willis et al25 reported that volar locking technology conferred a significant increase (p⬍0.01) in resistance to fracture gap motion compared with nonlocking plate technology. In our study, postoperative reduction was maintained by VLP. Because this system allows patients to start early mobilization safely, it enables them to rapidly regain independence in activity of daily living. VLP resulted in earlier recovery of range of motion and grip strength after surgery compared with IFP. It is reported that radial shortening with positive UV after distal radius fracture causes poor functional outcome.26,27 Aro and Koivunen26 reported poor results in 4% of patients with UVⱕ3 mm, 25% at UV more than 3 mm but less than 5 mm, and 31% at
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UVⱖ5 mm. We have to avoid radial shortening with UV more than 3 mm to achieve good clinical results after distal radius fracture. Surgically corrected UV was lost in the IFP group under our postoperative protocol. In the IFP group, the final UV values were 4 mm in patients with baseline UV⬎5 mm and 3 mm in cases with BMD⬍70% of YAM. Both the baseline UV⬎5 mm (p⬍0.01) and BMD⬍70% (p⬍0.05) of YAM were significant and independent preoperative factors that aggravated the final UV in the IFP group. Even in such cases, however, VLP maintained postoperative reduction under early mobilization without the use of a plaster cast after surgery. One limitation of the present study is that it was not a randomized, controlled trial but a prospective cohort. We planned this study as a sequential comparison prospectively because we considered that it was more difficult for us to achieve the agreement of patients’ participation in a randomized, controlled trial than in a prospective, consecutive study and that we could collect a sufficient number of patients in a shorter period of time. Another limitation is the small number of patients. The sample size, however, which was calculated with a power analysis, satisfied conventional levels of statistical significance. The other limitation was the short follow-up period. We considered that most patients with distal radius fractures could reach the steady state of radiological findings, range of motion, and grip power within 6 months after surgery. The initial protocol involved follow-up examination of all patients for more than 6 months after surgery because we were concerned that the patients eliminated from the study would increase in number after 6 months. This was an efficacy study in which the physicians had a great deal of experience with surgical correction of distal radius fractures. The results of this study present useful information for physicians choosing a surgical treatment for distal radius fractures in patients over 60 years of age. Intrafocal pinning should be avoided for elderly patients with baseline UV⬎5 mm at the time of injury and BMD⬍70% of YAM. Instead, we recommend the use of volar locking plate, as it enhances early recovery of range of motion and grip strength. Received for publication April 23, 2007; accepted in revised form July 10, 2007. No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article. Corresponding author: Akinori Sakai, MD, PhD, Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 8078555, Japan; e-mail: [email protected].
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Copyright © 2007 by the American Society for Surgery of the Hand 0363-5023/07/32A09-0005$32.00/0 doi:10.1016/j.jhsa.2007.07.005
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26.
27.
the bone mineral density of the lumbar spine and hip. J Hand Surg 2004;29B:473– 476. Orimo H, Hayashi Y, Fukunaga M, Sone T, Fujiwara S, Shiraki M, et al.; Osteoporosis Diagnostic Criteria Review Committee: Japanese Society for Bone and Mineral Research. Diagnostic criteria for primary osteoporosis: year 2000 revision. J Bone Miner Metab 2001;19:331–337. Kanis JA, Melton LJ III, Christiansen C, Johnston CC, Khaltaev N. The diagnosis of osteoporosis. J Bone Miner Res 1994;9:1137–1141. Osada D, Fujita S, Tamai K, Iwamoto A, Tomizawa K, Saotome K. Biomechanics in uniaxial compression of three distal radius volar plates. J Hand Surg 2004;29A:446 – 451. Osada D, Fujita S, Yamaguchi T, Tamai K, Saotome K. Volar-locking plate fixation for unstable distal radius fractures in elderly patients. J Jpn Soc Surg Hand 2005;22:406 – 410. Motulsky H. Intuitive biostatistics. (First Japanese Edition). Tokyo: Medical Sciences International, 1997:196 –205. Graff S, Jupiter J. Fracture of the distal radius: classification of treatment and indications for external fixation. Injury 1994;25 Suppl 4:S-D14 –25. Metz VM, Gilula LA. Imaging techniques for distal radius fractures and related injuries. Orthop Clin North Am 1993; 24:217–228. Goldfarb CA, Yin Y, Gilula LA, Fisher AJ, Boyer MI. Wrist fractures: what the clinician wants to know. Radiology 2001; 219:11–28. Itoh S, Tomioka H, Tanaka J, Shinomiya K. Relationship between bone mineral density of the distal radius and ulna and fracture characteristics. J Hand Surg 2004;29A:123– 130. Drobetz H, Bryant AL, Pokorny T, Spitaler R, Leixnering M, Jupiter JB. Volar fixed-angle plating of distal radius extension fractures: influence of plate position on secondary loss of reduction - a biomechanic study in a cadaveric model. J Hand Surg 2006;31A:615– 622. Willis AA, Kutsumi K, Zobitz ME, Cooney WP III. Internal fixation of dorsally displaced fractures of the distal part of the radius. A biomechanical analysis of volar plate fracture stability. J Bone Joint Surg 2006;88A:2411–2417. Aro HT, Koivunen T. Minor axial shortening of the radius affects outcome of Colles’ fracture treatment. J Hand Surg 1991;16A:392–398. Fujii K, Henmi T, Kanematsu Y, Mishiro T, Sakai T, Terai T. Fractures of the distal end of radius in elderly patients: a comparative study of anatomical and functional results. J Orthop Surg (Hong Kong). 2002;10:9 –15.
Purpose: To compare the clinical and radiological outcomes of intrafocal pinning (IFP) and volar locking plating (VLP) of dorsally angulated, unstable distal radius fractures in elderly patients. Methods: The subjects were 62 consecutive patients over 60 years of age with dorsally angulated, unstable distal radius fractures treated with IFP or VLP. Bone mineral density (BMD) of the lumbar spine was measured by dual-energy x-ray absorptiometry at first examination. The range of motion and grip strength were measured at follow-up examinations, and ulnar variance (UV) was measured on radiographs at baseline and follow-up postoperative examinations. Results: There were no notable differences in gender, age, follow-up period, baseline UV, BMD, and AO classification between IFP and VLP groups. There was no difference between the UV in VLP immediately after surgery and at the final follow-up examination; however, IFP showed a significant loss of reduction as measured by UV. In patients with UV more than 5 mm or BMD less than 70% of young adult mean (YAM) at first examination, UV increased again at the final follow-up examination in IFP, while surgically corrected UV was maintained in VLP, independent of the degree of baseline UV and BMD. VLP resulted in earlier recovery of postoperative range of motion and grip strength compared with IFP. The range of flexion and the grip strength value were significantly larger in VLP at final examination. Conclusions: VLP, but not IFP, can maintain surgically corrected UV in distal radius fractures, independent of the degrees of initial UV and BMD. VLP enhances earlier recovery in range of motion and grip strength than IFP. (J Hand Surg 2007;32A:1385–1392. Copyright © 2007 by the American Society for Surgery of the Hand.) Type of study/level of evidence: Therapeutic II. Key words: Radius fracture, intrafocal pinning, volar locking plate, ulnar variance, osteoporosis.
istal radius fractures are common in the elderly, and at least some benefit from internal fixation. Various surgical techniques are used for the treatment of dorsally displaced, unstable distal radius fractures, such as percutaneous pinning,1,2 intramedullary pinning3,4 or nail,5,6 external fixation,7,8 and internal fixation with various plates.9,10 There is no standardized protocol,
D
however, for the management of these fractures.11 Thus, there is a need for objective comparisons of the various treatment alternatives for the surgical treatment of these fractures. The ideal surgical method should maintain anatomical position and ensure early mobilization. Anatomical reduction with stable fixation is the preferable treatment of unstable distal radius fractures.
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Percutaneous pinning techniques with or without external fixation are historically the most popular. Recent studies, however, described the usefulness of volar locking screw/plate implants, which can stabilize cancellous, fragmented bone for the treatment of dorsally displaced, unstable distal radius fractures in elderly patients.9,12 The differences in outcomes between percutaneous pinning and volar locking plating are not well reported, so we present postoperative data on serial radiological changes and functional recovery comparing these two methods. Elderly patients with distal radius fractures frequently have low bone mineral density (BMD). Low BMD in women is a risk factor for low-energy Colles’ fractures.13 More than half of elderly women with a distal radial fracture have osteoporotic BMD values for the lumbar spine or hip.14 Osteoporosis is characterized by the presence of both low BMD and disruption of normal bone architecture that leads to bone fragility. In Japan, osteoporosis is diagnosed when BMD falls below 70% of the young adult mean (YAM) (age 20 – 44 years).15 This diagnostic criterion is equivalent to that proposed by the World Health Organization, which defines osteoporosis as a BMD value ⬍2.5 SD of YAM (age 20 – 40 years).16 The subjects of this study included patients with and without osteoporosis. Our study investigated whether the degree of bone fragility as measured by BMD should be a factor in selecting the surgical procedure for distal radius fractures. We prospectively and consecutively treated elderly patients with dorsally angulated, unstable distal radius fractures using intrafocal pinning (IFP) (Kapandji’s method1) from 2002 to 2003 and volar locking plating (VLP) in 2004. The plate used in this study was the distal radius volar locking plate system (DRV2, Mizuho Co., Tokyo, Japan) developed by Osada et al.17,18 In this study, we compared the clinical and radiological outcomes of the two treatment modalities of IFP and VLP.
Materials and Methods Subjects All patients with distal radius fractures were initially managed with closed reduction and splinting, and patients with unstable or unsuccessful reduced fractures underwent surgery. The indications for internal fixation included dorsal angulation ⬎10°, radial inclination angle ⬍15°, or ulnar variance (UV) ⬎3 mm. Osteoporosis was not a criterion for inclusion into the study. The enrolled subjects were 62 consecutive patients over 60 years of age with 62 dor-
sally angulated, unstable distal radius fractures treated with IFP for 31 patients and VLP for 31 patients from 2002 to 2004 at our institution. We prospectively treated consecutive patients with IFP from 2002 to 2003 and VLP in 2004. All patients consented to the study participation at the first visit, and all aspects of the study were approved by the institutional review board. We observed that the final UV value in IFP was approximately 2.5 mm and that in VLP was approximately 0.5 mm based on our clinical experience before starting the present study. To determine the number of patients required for meaningful statistical analysis, we performed power analysis before the conduct of the study.19 We used 2.0 as the minimum difference we wished to detect as significant, assuming ␣⫽0.05 (two-sided) and ⫽0.2 (power⫽80%). The analysis identified 25 as the minimum number of subjects required for each group. Subjects of the IFP group were 2 men and 29 women, and the VLP group comprised 5 men and 26 women (Table 1). The mean age of the patients at the time of surgery was 71 years (range, 60 – 87) for the IFP group, and 70 years (range, 60 –94) for the VLP group. All patients were followed up regularly with physical and radiological examinations for at least 6 months after surgery. The mean period of follow-up was 13 months (range, 6 –30) for the IFP group and 11 months (range, 6 –23) for the VLP group. UV on baseline radiographs after injury was ⬎5 mm in 7 patients and ⱕ5 mm in 24 patients of the IFP group, and 11 and 20 patients of the VLP group, respectively. There were no notable differences in gender, age, follow-up period, or baseline UV between IFP and VLP groups. BMD of the lumbar spine (L2-L4) was measured by dual-energy x-ray absorptiometry (QDR-4500, Hologic Inc., Bedford, MA) at the first visit. In the IFP group, the BMD/YAM ratio was ⱖ80% in 9 patients, 70 – 80% in 14 patients, and ⬍70% in 8 patients. In the VLP group, the corresponding numbers of patients were 8, 16, and 7. According to the AO classification scheme),20 25 fractures were considered type A (extra-articular fractures involving neither the radiocarpal nor the radioulnar joint) fractures (3 A2 and 22 A3) and 6 type C (complex articular fractures affecting the joint surface and metaphyseal area) fractures (5 C1 and 1 C2) for the IFP group, and 27 type A fractures (7 A2 and 20 A3) and 4 type C fractures (3 C1 and 1 C2) for the VLP group. Articular fractures were identified in 6 patients of the IFP group and 4 patients of the VLP
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Table 1. Patient Characteristics Number of cases Gender (male:female) Age (years) Follow-up period (months) UV (number of cases) ⬎ 5 mm ⱕ 5 mm BMD (number of cases) ⬍ 70% of YAM ⱖ 70% of YAM AO classification type (number of cases) A C
IFP
VLP
p Value
31 2 : 29 70.7 (60–87) 13 (6–30)
31 5 : 26 69.9 (60–94) 11 (6–23)
NS NS NS
7 24
11 20
NS
8 23
7 24
NS
25 6
27 4
NS
The p value was determined by Mann-Whitney U test for age and follow-up period and by chi-square test for gender, baseline UV, BMD, and AO classification type. Values of age and follow-up period represent the mean and (range). NS: not significant.
group. The intra-articular step-off of these patients, however, was not greater than 2 mm. There were no notable differences in BMD and the AO classification between the IFP and VLP groups. Surgical Treatment Surgery was performed under a brachial plexus block anesthetic. IFP was based on the procedure described by Kapandji.1 We inserted three K-wires (1.8-mm [0.071-in.] diameter) into the fracture site of the radius with fracture reduction. One was inserted into the proximal portion of Lister’s tubercle and another between the tendons of the extensor digitorum communis. These 2 wires were placed dorsal to volar. The other wire was inserted between the tendons of the extensor pollicis brevis and extensor carpi radialis longus. This wire was placed radial to ulnar, entering at the radial styloid. The mean duration of surgery was 22 minutes. A below-elbow plaster cast was applied for 3 weeks after surgery. The K-wires were removed 6 weeks after surgery. Active finger motion was encouraged early after surgery, and forearm rotation was initiated within 4 to 5 days after surgery. Active and active-assisted motion of the wrist joint was started to patient tolerance after the plaster cast was removed. Passive exercises were started 6 weeks after surgery and continued until 12 weeks after surgery. VLP was performed with a longitudinal skin incision along the tendon of the flexor carpi radialis from the distal palmer wrist crease to approximately 6 cm proximally. The sheath of the flexor carpi radialis tendon was incised, and the tendon and flexor pollicis longus muscle were retracted ulnarly. The radial bor-
der of the pronator quadratus muscle was cut longitudinally. The volar aspect of the radius was exposed subperiosteally. A volar locking plate was placed directly on the radius after fracture reduction. A plate used in this study was the distal radius volar locking plate system (DRV2, Mizuho Co., Tokyo).17,18 No bone grafting was used. After fixation, the pronator quadratus was repaired over the plate with absorbable suture. The mean duration of surgery was 50 minutes. No plaster cast was applied after surgery. A removable wrist brace was used for support between exercises for 3 weeks after surgery. Active finger motion was encouraged early after surgery. Forearm rotation and active and active-assisted motion of the wrist joint were started within 4 –5 days after surgery to patient tolerance. Passive exercises started 6 weeks after surgery and continued until 12 weeks after surgery. Outcome Evaluations The degree of fracture displacement was assessed by measuring UV, radial inclination angle, and dorsal angulation, based on standard anteroposterior and lateral projection radiographs taken on the basis of the quality criteria described by Metz and Gilula21 and Goldfarb et al22 at the first visit, immediately after surgery, and at the final visit. In addition, we checked the wrist and forearm range of motion (extension, flexion, pronation, and supination) and grip strength at 3, 4, 6, 8, and 12 weeks and at final examination after surgery for the IFP group and at 1 and 2 weeks as well as after surgery for the VLP group.
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Analysis of the Radiological Data After Dividing Patients into Subgroups We analyzed the radiological data of UV, radial inclination angle, and dorsal angulation by dividing patients into subgroups, respectively, when there were notable differences in the respective final radiological outcomes between IFP and VLP groups. We divided patients into two subgroups based on the degree of baseline UV and BMD at first examination. First, the subgroups were baseline UV ⬎5 mm and baseline UV ⱕ5 mm. Second, the subgroups were BMD ⱖ70% of YAM and BMD ⬍70% of YAM. Preoperative Factors That Could Contribute to the Final Radiological Outcomes We investigated the preoperative factors that could influence the final outcome when there were notable differences in the respective final radiological outcomes between IFP and VLP groups. The candidate preoperative factors were age, baseline UV, BMD, and the AO classification of the fractures. Statistical Analysis Results were expressed as mean ⫾ standard error of the mean (SEM). Differences between IFP and VLP were evaluated using the Mann-Whitney U test for age, follow-up period, and UV values at each time point, and using the chi-square test for gender, baseline UV, BMD, and AO classification type. Differences in UV values immediately after surgery and at the final follow-up examination were evaluated using paired Student’s t-test. The significant preoperative factors for final UV in IFP were determined by logistic regression analysis. A p value of ⬍0.05 was considered significant. Statistical analysis was performed using StatView 5.0 software (SAS Institute, Cary, NC).
Results General Results and Complications Sound union occurred in all cases. Rupture of the tendon of extensor pollicis longus occurred in 2 cases of the IFP group and 1 case of the VLP group. The cause of this rupture following the use of a volar plate was not elucidated. Pin track superficial infection at the sites of K-wire insertion occurred in 4 cases of the IFP group, but all cases showed excellent healing after removal of the wires. None of the patients developed deep infection or complex regional pain syndrome.
UV (mm) 6 IFP 4
VLP
++
2
*
0 -2 initial
immediately after surgery
final
Figure 1. Changes in UV. Data are mean ⫾ SEM. *p⬍0.05 vs. IFP by Mann-Whitney U test. ⫹⫹p⬍0.01 vs. immediately after surgery in each group by paired Student’s t-test.
Radiological Findings For the IFP group, the mean degree of radial inclination was 24° immediately after surgery and 22° at the final follow-up examination. The respective values for the VLP group were 22° and 22°. The change in radial inclination was not statistically different between the two groups. The mean degree of dorsal angulation was 6° immediately after surgery and 4° at the final follow-up examination for the IFP group, and 8° and 4° for the VLP group, respectively. There was no difference in dorsal angulation between the two groups. The mean UV was 0 mm immediately after surgery and 2 mm at the final follow-up examination for the IFP group and was 0 mm and 1 mm for the VLP group (Fig. 1). There were no differences between the UV in VLP immediately after surgery and at the final follow-up examination; however, IFP showed a significant loss of reduction (p⬍0.01), as measured by UV. Analysis of the Radiological Data After Dividing Patients into Subgroups There was a significant difference (p⬍0.05) in the final UV between IFP and VLP groups. Thus, we analyzed the UV data by dividing patients into two subgroups. For the IFP subgroup with baseline UVⱕ5 mm (UVⱕ5-IFP group), the mean length of UV was 2 mm at injury, 1 mm immediately after surgery, and 1 mm at the final follow-up examination, compared with 7 mm, 1 mm, and 4 mm, respectively, for the UV⬎5-IFP group (Fig. 2A). The UV value determined at the final follow-up examination was significantly higher (p⬍0.01) in the UV⬎5-IFP group than that of the UVⱕ5-IFP group. For the VLP subgroup with baseline UVⱕ5 mm (UVⱕ5-VLP group), the mean length of UV was 2 mm at injury, 0 mm immediately after surgery, and 1 mm at the final
Oshige et al / Pinning Versus Plating for Distal Radius Fractures UV (mm)
UV (mm) 12
12
10 8
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immediately after surgery
final
initial
B
immediately after surgery
final
Figure 2. Changes in UV in patients with baseline UV ⬎5 mm or ⱕ5 mm. (A) IFP. (B) VLP. Data are mean ⫾ SEM. **p⬍0.01 vs. subgroup with UVⱕ5 mm in each group, #p ⬍0.05, ##p ⬍0.01 vs. respective subgroups of IFP by Mann-Whitney U test. ⫹p ⬍0.05, ⫹⫹p⬍0.01 vs. immediately after surgery of respective subgroups in each group by paired student’s t-test.
Preoperative Factors That Could Contribute to the Final Radiological Outcomes There was a significant difference (p⬍0.05) in the final UV between IFP and VLP groups. The final UV was not adequately maintained in certain subgroups of the IFP group, while VLP maintained the surgically corrected UV, independent of the degree of baseline UV and BMD. The preoperative factors that significantly contributed to the final UV in the IFP group were baseline UV⬎5 mm and BMD⬍70% of YAM (Table 2). The relative risk was 2.90 (95% confidence interval [CI]: 1.39 – 6.06) in cases with baseline UV⬎5 mm and 1.59 (95% CI: 1.02 – 2.47) in cases with BMD⬍70% of YAM. Age and AO classification of the fractures were not notable independent factors that aggravated the final UV in the IFP group. There was no relationship between BMD and AO classification.
follow-up examination, compared with 8 mm, 0 mm, and 1 mm, respectively, for the UV⬎5-VLP group (Fig. 2B). The final UV values were not different between the two VLP subgroups. The final UV values of the VLP group were significantly lower than those of the IFP group for both the UVⱕ5 mm and UV⬎5 mm subgroups. For the IFP group, the mean length of UV of the subgroup with BMDⱖ70% of YAM at first examination (ⱖ70% BMD-IFP group) was 2.7 mm at injury, 0.2 mm immediately after surgery, and 2 mm at the final follow-up examination, and 4 mm, 1 mm, and 3 mm, respectively, in the ⬍70% BMD-IFP group (Fig. 3A). On the other hand, for the VLP group, the mean length of UV was 3 mm at injury, 0 mm immediately after surgery, and 1 mm at the final follow-up examination in the ⱖ70% BMD-VLP group, and 5 mm, 0 mm, and 1 mm, respectively, in the ⬍70% BMD-VLP group (Fig. 3B). The final UV values were not different between the two VLP subgroups, while those of the VLP group were significantly lower (p⬍0.05) than the IFP group for both BMD ⱖ70% and ⬍70% of YAM.
Range of Motion VLP resulted in earlier recovery of postoperative range of motion, including extension (Fig. 4A) and flexion (Fig. 4B) of the wrist joint and pronation (Fig.
UV (mm)
UV (mm) 10
10 BMD 㸱 70% of YAM
8
BMD Ӎ 70% of YAM
6
* +
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8
BMD Ӎ 70% of YAM
6 4 2
#
0
#
-2 initial
immediately after surgery
final
B
initial
immediately after surgery
final
Figure 3. Changes in UV in patients with BMD ⬍70% of YAM or ⱖ70% of YAM. (A) IFP. (B) VLP. Data are mean ⫾ SEM. *p ⬍0.05 vs. subgroup of BMDⱖ70% of YAM in each group, #p ⬍0.05 vs. respective subgroups of IFP by Mann-Whitney U test. ⫹p ⬍0.05, ⫹⫹p ⬍0.01 vs. immediately after surgery of respective subgroups in each group by paired student’s t-test.
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Table 2. Preoperative Factors That Aggravated the Final UV in IFP Preoperative Factors UV at the initial radiographs ⬎ 5 mm BMD at the initial examination ⬍ 70% of YAM
p Value
Relative Risk
95% CI
⬍0.01
2.90
1.39-6.06
⬍0.05
1.59
1.02-2.47
The p value, relative risk, and 95% CI were determined by logistic regression analysis. CI, confidence interval.
and grip strength compared with IFP. Because there are many surgical procedures but no strict guidelines for treatment of dorsally angulated, unstable distal radius fractures and no selection criteria for surgery, treatment depends on the surgeons’ choice. Under these circumstances, our study provides new data that VLP is superior in maintaining earlier postoperative reduction compared with IFP in elderly patients with initial radial shortening and UVⱖ5 mm or osteoporosis with BMD⬍70% of YAM at first examination. The ability of IFP to maintain postoperative reduction is poorer than VLP.2,10 There is no information on the importance of BMD on maintenance of earlier postoperative reduction by surgery for distal radius fractures, although it is reported that the BMD in the contralateral distal radius is an important prognostic parameter of possible deformity of the radius after closed reduction and casting.23 In elderly patients, bone strength decreases in proportion with reduction
4C) and supination (Fig. 4D) of the forearm, compared with IFP. The degree of flexion was significantly larger (p⬍0.01) in the VLP group than in the IFP group at the final examination. Grip Strength VLP resulted in earlier recovery of grip strength after surgery compared with IFP (Fig. 5). Recovery to the 50% level of the opposite uninjured side was achieved in approximately 3 weeks in the VLP group and in approximately 12 weeks in the IFP group. The grip strength of the VLP group was significantly larger (p⬍0.01) than that of the IFP group at the final examination. Discussion The present study demonstrated that in elderly patients, VLP, but not IFP, could maintain postoperative reduction, independent of the degree of UV and BMD at baseline, and that VLP was associated with early postoperative recovery of the range of motion
Degree of extension (% of the opposite uninjured side) 100 㸟㸟
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Figure 4. Serial postoperative changes in range of motion. (A) Extension. (B) Flexion. (C) Pronation. (D) Supination. Data are mean ⫾ SEM. *p ⬍0.05, **p ⬍0.01 vs. IFP by Mann-Whitney U test.
Oshige et al / Pinning Versus Plating for Distal Radius Fractures Grip strength (% of the opposite uninjured side) 100 IFP
80
㸟㸟
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Figure 5. Serial postoperative changes of grip strength. Data are mean ⫾ SEM. **p ⬍0.01 vs. IFP by Mann-Whitney U test.
in BMD, and fractures of the distal radius, an osteoporotic fracture, frequently occurs. BMD is a major determinant of bone strength. The radius seems to be fractured with more severe displacement and shortening in osteoporotic patients than in nonosteoporotic patients, even when the same force is applied to the bone. In this study, the baseline UV value at injury was 5 ⫾ 1 mm in patients with BMD⬍70% of YAM and 3 ⫾ 0 mm in patients with BMDⱖ70% of YAM. Thus, the baseline UV value of patients with osteoporosis was significantly larger (p⬍0.05) than that of patients without osteoporosis. It seems reasonable to select surgical procedures based on the level of fracture displacement and the BMD of the patient. VLP is a reliable plating system for the fixation of unstable distal radius fractures. Previous studies examined biomechanical changes in distal radius fractures stabilized by VLP. Drobetz et al24 reported that the subchondral plate-screw-bone constructs of VLP systems showed significantly greater rigidity, indicating higher resistance to postoperative loads and displacement force, and resulted in the maintenance of radial length after surgery. Willis et al25 reported that volar locking technology conferred a significant increase (p⬍0.01) in resistance to fracture gap motion compared with nonlocking plate technology. In our study, postoperative reduction was maintained by VLP. Because this system allows patients to start early mobilization safely, it enables them to rapidly regain independence in activity of daily living. VLP resulted in earlier recovery of range of motion and grip strength after surgery compared with IFP. It is reported that radial shortening with positive UV after distal radius fracture causes poor functional outcome.26,27 Aro and Koivunen26 reported poor results in 4% of patients with UVⱕ3 mm, 25% at UV more than 3 mm but less than 5 mm, and 31% at
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UVⱖ5 mm. We have to avoid radial shortening with UV more than 3 mm to achieve good clinical results after distal radius fracture. Surgically corrected UV was lost in the IFP group under our postoperative protocol. In the IFP group, the final UV values were 4 mm in patients with baseline UV⬎5 mm and 3 mm in cases with BMD⬍70% of YAM. Both the baseline UV⬎5 mm (p⬍0.01) and BMD⬍70% (p⬍0.05) of YAM were significant and independent preoperative factors that aggravated the final UV in the IFP group. Even in such cases, however, VLP maintained postoperative reduction under early mobilization without the use of a plaster cast after surgery. One limitation of the present study is that it was not a randomized, controlled trial but a prospective cohort. We planned this study as a sequential comparison prospectively because we considered that it was more difficult for us to achieve the agreement of patients’ participation in a randomized, controlled trial than in a prospective, consecutive study and that we could collect a sufficient number of patients in a shorter period of time. Another limitation is the small number of patients. The sample size, however, which was calculated with a power analysis, satisfied conventional levels of statistical significance. The other limitation was the short follow-up period. We considered that most patients with distal radius fractures could reach the steady state of radiological findings, range of motion, and grip power within 6 months after surgery. The initial protocol involved follow-up examination of all patients for more than 6 months after surgery because we were concerned that the patients eliminated from the study would increase in number after 6 months. This was an efficacy study in which the physicians had a great deal of experience with surgical correction of distal radius fractures. The results of this study present useful information for physicians choosing a surgical treatment for distal radius fractures in patients over 60 years of age. Intrafocal pinning should be avoided for elderly patients with baseline UV⬎5 mm at the time of injury and BMD⬍70% of YAM. Instead, we recommend the use of volar locking plate, as it enhances early recovery of range of motion and grip strength. Received for publication April 23, 2007; accepted in revised form July 10, 2007. No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article. Corresponding author: Akinori Sakai, MD, PhD, Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 8078555, Japan; e-mail: [email protected].
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Copyright © 2007 by the American Society for Surgery of the Hand 0363-5023/07/32A09-0005$32.00/0 doi:10.1016/j.jhsa.2007.07.005
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