Table 2.
Findings from selected studies.
| Study | No. of Hips | Age (mean, range) | Follow-Up (mo, mean, range) | Arthroplasty Type & Approach | Preop Offset (mean, range) | Preop PROs | Postop Offset (mean, range) | Postop PROs | Additional Results |
|---|---|---|---|---|---|---|---|---|---|
| Bjordal et al.,12 2015 | 148 total, Group 1 (56 hips): lever arm restored to ≤ 5 mm of native Group 2 (95 hips): native lever arm was increased by ≥ 5 mm |
67.7 ± 10.9 | 12 | Anterior THA | Group 1, Group 2, p value: HHS (46.4 ± 16.7, 48.7 ± 18.6, 0.45), HOOS pain: (33.2 ± 16.0, 37.3 ± 18.0, 0.18) | Native Abductor Lever Arm: group 1: 61.6 ± 6.1 group 2: 55.8 ± 5.9 | Group 1, Group 2, p-value: HHS: (94.1 ± 9.7, 94.4 ± 10.6, 0.86), HOOS: (86.0 ± 19.0, 91.3 ± 12.6, 0.16) | ||
| Buecking et al.,21 2015 | 127 | 82 ± 7 (63-99) | 12 | Hemi-arthroplasty | Rotation-corrected femoral offset (mm): 41 ± 7.8 (17-67) | HHS: 68 ± 20, range (12-97) (IADL) 3.6 ± 3.2, range (0-8), (TUG): 39sec | Positive correlation between reconstructed offset and HHS, (r = 0.303, p = 0.025) and IADL (r = 0.325, p = 0.013) | ||
| Cassidy et al.,28 2012 | 249 Total, 31 had femoral offset < -5 mm compared to contralateral hip (decreased), 163 had between -5mm and 5 mm (normal), 55 had >5 mm (increased) | 62.3 | 12 | THA | (Decreased, normal, increased): SF-12P: 27.82 ± 6.04, 29.71 ± 7.86, 29.86 ± 8.84 SF-12 M: 46.99 ± 11.04, 50.63 ± 11.27, 50.77 ± 10.68 WOMAC pain: 29.68 ± 17.98, 43.39 ± 24.53, 43.63 ± 20.56 |
femoral offset < -5 mm compared to contralateral hip (decreased), between -5mm and 5 mm (normal), >5 mm (increased) | (Decreased, normal, increased): SF-12P: 43.3 ± 11.45, 46.99 ± 9.73, 44.39 ± 11.37 SF-12M: 52.11 ± 9.22, 54.14 ± 8.38, 54.5 ± 7.86 WOMAC pain: 86.5 ± 22.02, 91.69 ± 14.77, 92.87 ± 12.87 |
Decreased group exhibited inferior PROs compared to normal and increased group (P = 0.019) | |
| Clement et al.,23 2016 | 359 | 67 | 12 | THA | 45.9 | OHS: 20.5 ± 8.3 SF-12P: 31.8 ± 9.6 SF-12M 49.7 ± 12.3 EQ-5D: 0.388 ± 0.313 |
50.5 | OHS: 39.7 ± 8.8 SF-12P: 45.0 ± 11.0 SF-12M 48.3 ± 8.8 EQ-5D: 0.770 ± 0.259 |
Increased offset correlated to greater improvement in OHS |
| Ebied et al.,22 2005 | 54 Total, 16 hips had preop offset <40 mm (Group1) 38 hips had preop offset ≥40 mm (Group2) |
68 (29-84) | 106 (19.2-135.6) | Cemented THA | Group 1: 34 (30-39), Group 2: 46 (40-57) | Significant improvement (P < 0.05) in PMA scores in all patients following THA | |||
| Ji et al.,24 2017 | 100 | 79.5 ± 7.3 (59–94) | 12 | Hemi-arthroplasty | 37.4 ± 2.5 | Modified Barthel Index: 87.5 ± 6.7 (36-100) | 77% of group had femoral offset change of ± 20% (recovered) and 23% of group had femoral offset change ˃20% (unrecovered) | Recovered vs Unrecovered, HHS: 79.4 ± 15.6 vs 72.5 ± 23.1, Modified Barthel Index: 80.3 ± 13.5 vs 69.3 ± 20.5 | |
| Liebs et al.,14 2014 | 362 Total, 75 <5 mm between height adjusted offset and actual (low), 195 within 5 mm (nomal), 92 >5 mm (high) | 70 (35.2-90.5) | at 3,6,12,2-4 month intervals | THA | 41.0 (25.0-58.1) | low offset group reported statistically significant less pain (WOMAC) than normal or high offset groups at 6,12,24 months (P < 0.05) | |||
| Mahmood et al.,25 2016a | 222 Total, Group 1 (71 hips): Postoperative Offset <5 mm of contralateral hip (Decreased) Group 2 (73 hips): Offset within 5 mm of Contralateral Hip (Restored) Group 3 (78 hips): Offset >5 mm of Contralateral Hip |
71 | 12 | Posterolateral THA | WOMAC (Decreased, Restored, Increased): 61 ± 13, 60 ± 14, 61 ± 13 EQ-5D (Decreased, Restored, Increased): 0.44 ± 0.26, 0.43 ± 0.22, 0.51 ± 0.66 |
Decreased Group: <5 mm, Restored: within 5 mm, Increased >5 mm | WOMAC (Decreased, Restored, Increased): 20 ± 19, 15 ± 15,15 ± 14 EQ-5D (Decreased, Restored, Increased): 0.82 ± 0.19, 0.86 ± 0.17, 0.86 ± 0.19 |
Decreased group exhibited less postoperative abductor strength and greater use of walking aids (32% vs 21% vs 15%, p = 0.04) | |
| Sariali et al.,26 2014 | 28 Total hips: 9 had postop femoral offset decrease <15% (decreased), 14 had postoperative femoral offset within 15% (restored), and 5 had postoperative femoral offset increase >15% (increased) | 65.6 in decreased group 67.3 in restored group 72.4 in increased group |
12 | Primary THA | HHS (decreased, restored, increased): 36.6 (29-53), 34.4 (27-47) PMA (decreased, restored, increased): 10.7 (8-15), 10.6 (9-13), 9.4 (8-10) WOMAC (decreased, restored, increased): 53 (14-18), 54 (34-65), 54.4 (35-73) HOOS (decreased, restored, increased): 36.5 (23-52), 33.1 (18-45), 29.0 (20-45) |
Decreased Group: <15%, Restored: within 15%, Increased: >15% | HHS (decreased, restored, increased): 87.9 (69-100), 92.4 (79-100), 92.7 (88-100) PMA (decreased, restored, increased): 16.3 (14-18), 16.8 (15-18), 16.8 (15-18) WOMAC (decreased, restored, increased): 7.4 (0-18), 8.2 (0-37), 4.0 (0-6) HOOS (decreased, restored, increased): 86.2 (64-100),90.9 (70-99), 94.2 (85-99) |
Reduced range of motion at the knee (p = 0.004) and lower swing speed in operated limb (p = 0.01); decrease in hip adduction in decreased group (P < 0.001) | |
| Takao et al.,27 2016 | 89 | 62 ± 12 (25-83) | 12 | mini-incision THA (32 anterolateral, 57 posterior) | 4 ± 6 (-19-24) | 34 ± 5 (22-47) | WOMAC pain: 0.9 ± 2.1 (0-14), WOMAC stiffness 0.7 ± 1.5 (0-10_, WOMAC physical function: 5.2 ± 7.4 (0-33) (NPRS): 0.6 ± 1.1 (0-7) |
Postop leg length discrepancy, abduction range of motion were correlated with cup-head separation postop leg length discrepancy was negatively correlated to cup-head separation |
(HHS): Harris Hip Score, (WOMAC): Western Ontario McMaster Universities Index, (OHS): Oxford Hip Score, (EQ-5D), the EQ-5D health questionnaire, (SF-12M, SF-12P): the mental and physical portions of the Short Form Survey, (HOOS): Hip disability and Osteoarthritis Outcome Score (HOOS), (PMA): Merle d'Aubigné-Postel Pain Score, (IADL): the Instrumental Activities of Daily Living, (TUG): Timed Up and Go, (NPRS): Numerical Pain Rating Scale (NPRS).
a
Used global offset = femoral offset + cup offset.