Necessity of grafting in scaphoid nonunion fixation: A comparative outcome analysis

Table 1 Demographic characteristics of the study participants, n (%)/mean ± SD

Variables	All participants (n = 44)	Fixation groups			Grafting subgroups
		Graft-less group (n = 21)	Graft-augmented group (n = 23)	P value	NVBG subgroup (n = 12)	VBG subgroup (n = 11)	P value
Age (years)	28.9 ± 6.6	26.3 ± 5.5	31.4 ± 6.7	0.009a	30.2 ± 6.6	32.6 ± 6.9	0.4
Gender
Male	40 (90.9)	20 (95.2)	20 (87)		12 (100)	8 (72.7)
Female	4 (9.1)	1 (4.8)	3 (13)	0.6	0 (0)	3 (27.3)	0.09
Affected side
Right	26 (59.1)	12 (57.1)	14 (60.9)		6 (50)	8 (72.7)
Left	18 (40.9)	9 (42.9)	9 (39.1)	0.3	6 (50)	3 (27.3)	0.06
Dominance
Non-dominant	16 (36.4)	9 (42.9)	7 (30.4)		4 (33.3)	3 (27.3)
Dominant	28 (63.6)	12 (57.1)	16 (69.6)	0.4	8 (66.7)	8 (72.7)	1.00
Previous traumatic event	23 (52.3)	9 (42.9)	14 (60.9)	0.2	8 (66.7)	6 (54.5)	0.6
SNU duration (month)	13.5 ± 6.6	13.1 ± 6.7	13.8 ± 6.6	0.7	14.8 ± 5.4	12.7 ± 7.8	0.4
SNU duration
< 1 year	21 (47.7)	11 (52.4)	10 (43.5)		2 (16.7)	8 (72.7)
≥ 1 year	23 (52.3)	10 (47.6)	13 (56.5)	0.5	10 (83.3)	3 (27.3)	0.01a
Fracture type
Cystic	31 (70.5)	15 (71.4)	16 (69.6)		6 (50)	10 (90.9)
Linear	13 (29.5)	6 (28.6)	7 (30.4)	0.8	6 (50)	1 (9.1)	0.03a
Bone resorption
< 5 mm	22 (50)	14 (66.7)	8 (34.8)		7 (58.3)	1 (9.1)
≥ 5 mm	22 (50)	7 (33.3)	15 (65.2)	0.03a	5 (41.7)	10 (90.9)	0.01a
Nonunion site
Waist	23 (52.3)	14 (66.7)	9 (39.1)		8 (66.7)	1 (9.1)
Proximal pole	21 (47.7)	7 (33.3)	14 (60.9)	0.06	4 (33.3)	10 (90.9)	0.005a
Smoking	23 (52.3)	11 (52.4)	12 (52.17)	0.97	9 (75)	3 (27.3)	0.11

^aP < 0.05.

NVBG: Non-vascularized bone graft; VBG: Vascularized bone graft; SNU: Scaphoid nonunion.

Table 2 Clinical and radiological outcomes following scaphoid nonunion management, n (%)/mean ± SD

Clinical and radiological findings	All participants (n = 44)	Fixation groups			Grafting subgroups
		Graft-less group (n = 21)	Graft-augmented group (n = 23)	P value	NVBG subgroup (n = 12)	VBG subgroup (n = 11)	P value
Operative time (minutes)	83.2 ± 35.9	47.6 ± 8.3	115.8 ± 11.8	< 0.001a	112.08 ± 15.3	120.00 ± 3.8	0.1
Surgical approach	Dorsal (n = 25), volar (n = 7), mini-dorsal (n = 12)	Mini-dorsal (n = 12), dorsal (n = 9)	Dorsal (n = 16), volar (n = 7)		Dorsal (n = 5), volar (n = 7)	Dorsal (n = 11)
Follow-up duration (month)	27.52 ± 3.1	28.0 ± 3.3	27.08 ± 2.9	0.3	27.9 ± 3.1	26.18 ± 2.7	0.3
Radiological findings
Healing
Nonunion	8 (18.2)	5 (23.8)	3 (13)	0.3	1 (8.3)	2 (18.2)	0.5
Union	36 (81.8)	16 (76.2)	20 (87)		11 (91.7)	9 (81.8)
Healing time (weeks)	14.1 ± 2.5 (n = 36)	16.2 ± 2 (n = 16)	12.5 ± 1.4 (n = 20)	< 0.001a	12.2 ± 1.25 (n = 11)	13 ± 1.6 (n = 9)	0.2
Clinical findings
Flexion ROM (°)	72.05 ± 6.4	73.5 ± 7.7	70.6 ± 4.5	0.1	70.8 ± 5.1	70.4 ± 4.1	0.8
Extension ROM (°)	63.75 ± 8.7	64.04 ± 10.2	63.4 ± 7.2	0.8	63.7 ± 6.4	63.2 ± 8.4	0.8
Total ROM (°)	135.8 ± 14	137.6 ± 17	134.1 ± 10.9	0.4	134.5 ± 10.9	133.6 ± 11.4	0.8
Radial deviation (°)	13.86 ± 3.8	15.5 ± 3.8	12.3 ± 3.1	0.004a	13.4 ± 2.4	11.09 ± 3.4	0.07
Ulnar deviation (°)	26.18 ± 6.8	30.9 ± 5.7	21.8 ± 4.6	< 0.001a	22.5 ± 4.8	21.2 ± 4.4	0.5
VAS
Median (min-max)	0 (0-3), 0.48 ± 0.9	0 (0-3), 0.38 ± 0.86	0 (0-3), 0.56 ± 1	0.5	0 (0-2), 0.16 ± 0.57	0 (0-3), 1 ± 1.2	0.5
Grip strength (kg)	44.56 ± 7.7	46.3 ± 7.04	43.02 ± 8.15	0.1	45.4 ± 3.1	40.4 ± 11.0	0.1
Grip strength ratio (%)	88.38 ± 5.9	91.3 ± 4.6	85.6 ± 5.7	< 0.001a	86.2 ± 5.2	85.1 ± 6.4	0.6
MMW score	90.8 ± 8.7	94.3 ± 8.2	87.6 ± 8.1	0.01a	90.4 ± 7.5	84.5 ± 7.8	0.08

^aP < 0.05.

NVBG: Non-vascularized bone graft; VBG: Vascularized bone graft; ROM: Range of motion; VAS: Visual analogue scale; MMW score: Mayo modified wrist score.

Table 3 Wrist function outcomes according to capsulotomy design, mean ± SD

Outcome variables	L-shaped capsulotomy (mini-dorsal approach) (n = 12)	Z-shaped capsulotomy (dorsal approach) (n = 25)	P value
Flexion ROM (°)	73.75 ± 7.7 (60-80)	71.6 ± 6 (55-80)	0.33
Extension ROM (°)	63.75 ± 12 (45-80)	64.2 ± 7.4 (50-80)	0.71
Total ROM (°)	137.5 ± 19.4 (110-160)	135.8 ± 12 (115-160)	0.52
Radial deviation (°)	15 ± 4.2 (8-20)	13.5 ± 3.8 (7-20)	0.29
Ulnar deviation (°)	29.9 ± 6.3 (20-35)	25.2 ± 6.9 (17-36)	0.07
VAS, median (min-max)	0 (0-3), 0.5 ± 1	0 (0-3), 0.48 ± 0.9	0.9
Grip strength (kg)	47.79 ± 3.6 (40-52.5)	42.96 ± 9.5 (20-53)	0.16
Grip strength ratio (%)	91.21 ± 5 (78.7-97.22)	87.92 ± 5.9 (71.9-97)	0.05

ROM: Range of motion; VAS: Visual analogue scale.

Table 4 Summary of case series reporting graft-less and graft-augmented fixation for scaphoid nonunion

Ref.	n (M:F)	Age (years)	Site	NU-duration	Approach	Follow-up	Clinical results	Healing time	Union rate/judgement
Graft-less fixation of scaphoid nonunion
Tada et al[14], 2021, retrospective study	19 (19:0)	29.2	Waist/PP/distal pole	14.8 weeks	Open (volar/dorsal)	NR	NR	3.7 months	17/19 (89.4%); X-ray, CT
Belloti et al[6], 2020, prospective study	12 (NR)	R: 27-40	Waist/PP	> 6 months	PC (volar/dorsal)	6 months	Flexion: 59.1°, extension: 48.7°; DASH: 6.99, PWRE: 7.97	NR	12/12 (100%); X-ray
Gurger et al[9], 2018, retrospective study	12 (10:2)	27	Waist/PP	7.6 months	PC (volar)	4.5 months	Flexion: 68°, extension: 66°; MMW: Excellent (n = 8) and good (n = 3)	3.8 months	11/12 (91.6%); X-ray, CT
Cha et al[8], 2017, retrospective study	15 (15:0)	28.9 ± 6.2	Waist	10.8 months	PC (volar)	12 months	Flexion: 69°, extension: 68°; DASH: 7 ± 3.9	5.5 months	15/15 (100%); X-ray, CT
Somerson et al[13], 2015, retrospective study	14 (13:1)	21.1 ± 10.6	Waist/PP	> 6 months	PC (volar/dorsal)	NR	Flexion: 73°, extension: 66°; DASH: 10.2	4.4 months	12/14 (85.7%); X-ray
Hegazy[10], 2015, case series	21 (17:4)	23	Waist	6.8 months	PC (volar)	25 months	Flexion: 74°, extension: 75°; DASH: 8	4 months	21/21 (100%); X-ray, CT
Capo et al[7], 2012, retrospective study	12 (11:1)	24	Waist	8.7 months	PC (volar/dorsal)	35 months	Flexion: 71°, extension: 66°; DASH: 6	4 months	11/12 (91.6%); X-ray
Mahmoud and Koptan[11], 2011, prospective study	27 (26:1)	28.3	Waist	18.2 months	PC (volar)	24.6 months	Flexion: 65.7°, extension: 60.7°; MMW: Excellent (n = 25) and good (n = 2)	2.9 months	27/27 (100%); X-ray, CT
Slade et al[12], 2003, prospective study	15 (14:1)	20	Waist/PP	9 months	PC (dorsal)	35 months	Flexion: 61°, extension: 49°; MMW: Excellent (n = 12) and good (n = 3)	3.5 months	15/15 (100%); X-ray
Graft-augmented fixation of scaphoid nonunion
Zondervan et al[27], 2024, retrospective	8 (8:0)	R: 16-28	Waist/PP	13 months	Cancellous DR BG (dorsal)	88.9 months	Flexion-extension arc: 143.7° ± 13.9°; median DASH: 2.9	12 weeks	85.7%; X-ray
Bhat et al[21], 2023, retrospective	38 (36:2)	28.7 ± 7.9	Waist/PP/distal pole	18.7 ± 4.9 weeks	Cancellous DR BG (volar)	22.2 months	Clinical outcome: NR; complications: Screw prominence (n = 1), grade 1 SNAC (n = 1)	15.7 ± 3 weeks	100%; X-ray
Ma et al[23], 2023, retrospective study	21 (18:3)	29.8 (R:18-46)	Waist/PP	38.3 months	IC BG (volar)	30.6 months	Flexion-extension arc: 118° ± 46°; PRWE: 14 ± 11, VAS: 3 ± 1, grip strength: 83% ± 26%	2.7 months (R: 2-4)	100%; X-ray
Schäfer et al[26], 2023, retrospective study	16 (16:0)	29 (R: 18-41)	Waist/PP	17 months (R: 6-60)	IC NVBG (volar/dorsal)	54 months	Flexion: 55°, extension: 50.1°; DASH: 2.36, grip strength: 99% (R: 72%-134%)	12.9 weeks (R: 11-15)	73%; X-ray, CT
Papatheodorou et al[25], 2021, retrospective study	64 (45:19)	27 (R: 19-42)	PP	23 months (R: 12-47)	DR VBG (dorsal)	32 months (R: 24-56)	Extension: 70°, flexion: 47°; MMW: 86, grip strength: 83%; complications: Persistent nonunion (n = 8), fibrous union (n = 1)	12 weeks	55/64 (86%); X-ray, CT
Manako et al[24], 2023, retrospective study	5 (5:0)	Med: 30; R: 18-41	Waist/PP	≥ 6 months	Zaidemberg’s DR VBG (volar/dorsal)	Med: 24 months; R: 8-30 months	MMW score: 95 points (R: 75-100)	4.25 months	4/5 (80%); X-ray
Keller et al[22], 2020, retrospective study	37 (36:1)	26.2	Waist/PP	51 months	MFC VG (volar ± dorsal assisted)	16 months	Flexion: 44° ± 16°, extension: 50° ± 15°; DASH: 19, PRWE: 30; grip strength: 44 kg, VAS: 5; complications: Hardware irritation necessitated implant removal (n = 4), late infection (n = 1), venous bleeding (n = 1), postoperative boutonniere-like deformity of thumb MCPJ (n = 1), delayed wound healing of volar approach (n = 1)	16 weeks (R: 12-22)	95%; X-ray, CT

M:F: Male-female ratio; NU: Nonunion; PP: Proximal pole scaphoid; NR: Not reported; CT: Computed tomography; R: Range; PC: Percutaneous; DASH score: Disabilities of Arm, Shoulder and Hand score; PWRE: Patient-rated Wrist Evaluation; MMW score: Mayo modified wrist score; DR: Distal radius; BG: Bone graft; SNAC: Scaphoid nonunion advanced collapse; IC: Iliac crest; VAS: Visual analogue scale; NVBG: Non-vascularized bone graft; VBG: Vascularized bone graft; Med: Median; MFC: Medial femoral condyle; VG: Vascularized graft; MCPJ: Metacarpo-phalangeal joint.

Table 5 Comparative studies evaluating graft-less vs graft-augmented fixation in scaphoid nonunion treatment

Ref.	Technique	Fixation device	Follow-up period	UR	HT	Clinical results	Complications
Graft-less vs graft-augmented fixation approaches for scaphoid nonunion
Current study	Mini-open screw fixation vs open curettage-grafting and screw fixation	Screw	27.52 ± 3.1 months	Graft-less fixation: 76.2%; fixation with BG: 87%	Graft-less fixation: 16.2 ± 2 weeks; fixation with BG: 12.5 ± 1.4 weeks (P < 0.001)	Graft-less fixation: Radial and ulnar tilt were greater (P = 0.004, P < 0.001, respectively). The grip strength ratio was also higher (P < 0.001). The MMW score was significantly better (P = 0.01). No relevant difference was noted between both groups regarding all other clinical outcomes	Nonunion: 5 patients (23.8%) after graft-less fixation and 3 patients (13%) with BG utilization. Graft-less group: Superficial wound infection (n = 1). Graft-augmented fixation: Mechanical radial sided wrist pain (n = 1)
Zengin N et al[20], 2023, retrospective	PC screw fixation (n = 16) vs open curettage-grafting and screw fixation (n = 17)	Screw	12 months	CRIF: 12/16 (75%); ORIF: 15/17 (88%) (P = 0.34)	CRIF: 11.8 weeks (8-17 weeks); ORIF: 12.5 weeks (9-17 weeks) (P = 0.41)	No statistically significant difference between both groups regarding postoperative flexion, extension ROMs, grip strength, and DASH score	Nonunion: 4 patients (25%) in the CRIF group and 2 patients (11%) in ORIF group
Zhong et al[28], 2023, retrospective	ORIF (group A) vs PC fixation (group B) vs PC fixation and PRP injection (group C)	Screw	12 months	Grade III SNU: No significant difference among the three groups (P = 0.52). URs were 90.9%, 100%, and 100%, respectively; grade IV SNU: UR was lower in group B than other groups. URs were 90%, 71.4%, and 90.9%, respectively	NR	Grade III SNU: No significant differences in VAS and MMW among the three groups. Grade IV SNU: Groups A and C had significantly lower VAS score and significantly higher MMW score, compared to group B. However, there was no significant difference between groups A and C	Grade III SNU: Nonunion in 9% of patients of group A. Grade IV SNU: Nonunion in 10%, 28.6%, and 9% of groups A, B, and C, respectively
Atilgan et al[19], 2022, retrospective	PC screw fixation (n = 19) vs NVBG and screw fixation (n = 24)	Screw	CRIF: 18.9 ± 1.8 months; ORIF: 16 ± 1.95 months	CRIF: 84.2% (n = 16); ORIF: 87.5% (n = 21)	CRIF: 17.19 ± 2.19 months; ORIF: 14.14 ± 1.82 months (P < 0.001)	MMW score: No statistically significant difference (P = 0.930). VAS score: Statistically significantly higher after CRIF than in ORIF (P = 0.012)	Nonunion: Three patients (15.7%) in the CRIF group, and 3 (12.5%) in the ORIF group
RCTs comparing employment of VBGs vs NVBGs in fixation of scaphoid nonunion
Fan et al[42], 2023	DR pedicled VBG (n = 20) vs IC NVBG (n = 18)	K-wires	One year	VBG: 19/20; NVBG: 16/18	HT was similar (VBG: 16 ± 22 weeks; NVBG: 17 ± 33 weeks)	There were no significant differences between the two groups in ROM, grip strength or functional scores	Nonunion: VBG group (3/20) following K-wire migration, and NVBG group (2/18)
Caporrino et al[41], 2014	DR VBG (n = 35) vs DR NVBG (n = 38)	K-wires	VBG: 29.4 months; NVBG: 28.6 months	No significant difference in UR (88% for VBG vs 80% for NVBG; P = 0.312)	VBG: Bony union was earlier by 12 days compared to NVBG (P = 0.002)	VBG group: Ulnar deviation was lower (P = 0.003), and radial deviation as well (P = 0.064). No significant differences were found for the remaining clinical outcomes	Nonunion rate in VBG group (11%) and NVBG group (20%)
Goyal et al[35], 2013	DR NVBG (n = 42) vs IC NVBG (n = 46)	Herbert screw	Group 1: 4.8 years; group 2: 5.2 years	No significant difference in UR (87.1% vs 86.5%)	Group 1: 4.2 months; group 2: 4.5 months	No significant difference regarding ROM, functional scores. Mean pain VAS scores were significantly different (group 2: 7.1, group 1: 4.2)	Iliac NVBG (local): Local hematoma required drainage (n = 1). Chronic pain for 3 months (n = 6); ASIS avulsion fracture (n = 1); nonunion in group 1 (12.8%), and group 2 (13.5%). Both groups (last visit): Tenderness over anatomical snuffbox in group 1 (n = 5), and group 2 (n = 6); degenerative changes in group 1 (n = 15), and group 2 (n = 14)
Ribak et al[40], 2010	DR VBG (n = 46) vs DR NVBG (n = 40)	Three K-wires	VBG: 24.4 months; NVBG: 21.7 months	Higher UR after VBG (89% vs 72%; P = 0.024). PP nonunion: Slightly higher UR with VBGs (90% vs 69%; P = 0.09)	VBG: Significantly earlier healing compared to NVBG (9.7 weeks vs 12 weeks; P = 0.0001)	VBG: Significantly higher functional outcome scores (P = 0.007)	Nonunion: 5/46 (11%) in VBG group and 11/40 (28%) in NVBG group
Braga-Silva et al[36], 2008	DR VBG (n = 35) vs IC NVBG (n = 45)	K-wires or screws	2.8 ± 1.4 years	Union occurred in all NVBG group and 32/35 of the VBG group (P = 0.135)	NVBG: 8.89 ± 2.26 months; VBG: 7.97 ± 3.06 months	There was no significant difference with respect to ROM or grip strength between the two groups	Nonunion in 3/35 (8.5%) of the VBG group with graft osteonecrosis

UR: Union rate; HT: Healing time; BG: Bone graft; MMW score: Mayo modified wrist score; PC: Percutaneous; CRIF: Closed reduction and internal fixation; ORIF: Open reduction and internal fixation; ROM: Range of motion; DASH score: Disabilities of Arm, Shoulder and Hand score; PRP: Platelet-rich plasma; SNU: Scaphoid nonunion; VAS: Visual analogue score; NVBG: Non-vascularized bone graft; K-wires: Kirschner wires; RCTs: Randomized control trials; VBG: Vascularized bone graft; DR: Distal radius; IC: Iliac crest; ASIS: Anterior superior iliac spine; PP: Proximal pole scaphoid.