Surgical treatment of femoral deformities in polyostotic fibrous dysplasia and McCune-Albright syndrome: A literature review

Table 1 Inclusion and exclusion criteria (population, intervention, comparator, outcome)

	Inclusion criteria	Exclusion criteria
Population	(1) Patients affected by polyostotic fibrous dysplasia or MAS; and (2) Patients affected by femoral deformities	(1) Patients affected by monostotic fibrous dysplasia; (2) Patients affected by PFD or MAS originally treated for fractures or impending fractures; (3) Patients affected by other kind of dysplastic pathologies as fibrocartilaginous dysplasia; and (4) Patients treated for deformities caused by PFD but not affecting femur
Intervention	(1) Osteotomies; and (2) Internal fixation by intramedullary nailing	(1) External fixation only; (2) Bone grafting or transplantations techniques only; and (3) Other surgical techniques
Comparison group	Internal fixation by peripheral plate	Not applicable
Outcome	Studies reporting clinical, radiographic evaluation	Not applicable
Time	Studies published from any date to 2021	Not applicable
Study type	(1) Cohort studies; (2) Case-control studies; and (3) Randomized control trials	(1) Letters; and (2) Case reports
Language	English	Other languages

MAS: McCune-Albright syndrome; PFD: Polyostotic fibrous dysplasia.

Table 2 Summary of literature data on surgical treatment of femoral deformities in polyostotic fibrous dysplasia and McCune-Albright syndrome

Ref.	Patients (femurs)	Type of deformities	Mean age at surgery	Surgical treatment	Length of follow-up	Results	Complications	Conclusions
Freeman et al[14], 1987	4 (6)	Complex	14.5 yr	Multiple osteotomies and fixation with Zickel nail	2.8 yr	Patients return to normal activities	Intraoperative fracture (1), Respiratory distress syndrome (1), Delayed union (1)	Definitive control of deformities and recurrent fracture
Ozaki et al[15], 1996	8 (11)	Coxa vara, Shepherd's crook deformity	6 yr	Valgus osteotomy in 2 cases + curettage and bone grafting	19.5 yr	Deformities continue to progress until puberty	None	The lesions stop progressing after puberty, with the change in activity of pathologic tissue from childhood to adult life
Keijser et al[16], 2001	7 (10)	Complex	14.5 yr	Several corrective osteotomies + curettage, cryosurgery and grafting with definitive I.M. fixation	6 yr	Progression of the deformities in patients with MAS	None	Functional outcomes of extended lesions are satisfactory although some lesions need multiple procedures
Ippolito et al[17], 2002	7 (10)	Complex	17 yr	Single or multiple osteotomies and fixation with UFN nail with spiral blade	2 yr	All patients were painless and able to walk, one with brace and another with crutches	Delayed union (1)	Provide mechanical support to the weak and fragile dysplastic bone through intramedullary nailing
O'Sullivan et al[18], 2002	5 (10)	Complex	8.6 yr	Elongating intramedullary rods + biphosphonates	> 2 yr	Improvement of quality of life, decreasing pain and fracture rate and improving walking ability	None	Elongating rod without stabilization of the femoral neck is effective but doesn't prevent coxa vara
Jung et al[19], 2006	5 (7)	Shepherd's crook deformity	24 yr	Multiple osteotomies and I.M. nailing with neck cross pinning	2.5 yr	All patients were able to return to normal activities of daily living	Loosening of the distal locking screw (1)	Good correction of progressing shepherd's crook deformity and prevention of recurrences and fractures
Yang et al[20], 2010	7 (8)	Coxa vara, Shepherd's crook deformity	22.7 yr	Valgus osteotomy, curettage, massive allograft and I.M. nailing with neck cross pinning	6.2 yr	Correction of coxa vara from 75° to 120°. No progression of deformity	None	The device represents the first choice of internal fixation, improving limb function and preventing fractures. Good incorporation of allografts
Li et al[21], 2013	12 (12)	Coxa vara, Shepherd's crook deformity	14.3 yr	Valgus osteotomy stabilized by DHS plate	1.5 to 10.6 yr	Correction of coxa vara from 89° to 129°	Fracture below the plate (1)	Restore the neck-shaft angle and the mechanical alignment of the femur and improve function
Kushare et al[22], 2014	5 (5)	Coxa vara, Shepherd's crook deformity	21.6 yr	Valgus osteotomy stabilized with different devices (plate, I.M. nail, E.F.)	2.2 yr	Satisfactory in 3 patients and unsatisfactory in 2 for persistent pain	Loosening of External Fixator (1)	I.M. implants with neck cross pinning are the preferable method of stabilizing osteotomies in shepherd's crook deformities
Ippolito et al[23], 2015	11 (12)	Complex	14 yr	Two stages: (1) Valgus osteotomy for correction of coxa vara and hip plate; and (2) Definitive fixation by I.M. nail with spiral blade	4.5 yr	Neck-shaft angle and shepherd's crook deformities were fully corrected	Cut out of the spiral blade (2), Plate‘s screw loosening (1), Fracture below the plate (1)	Restore femoral alignment, pain relief and gait improvement, avoiding complications related to peripheral plates
Benedetti et al[24], 2015	5 (8)	Complex	6 yr	Valgus osteotomy stabilized by I.M. nail with spiral blade	3 yr	Correction of deformities in all cases. Loss of coxa vara correction in 2 cases. Nail breakage in one case	Nail breaking below the spiral blade (1)	Proximal humeral nail connected to a spiral blade may represent a useful device to fix deformities in PFD in young children
Hefti et al[25], 2017	13 (15)	Shepherd's crook deformity	14.5 yr	Corrective osteotomy stabilized by a custom made retrograde intramedullary nail	4.5 yr	Most patients were pain free. All patients but one were able to walk, 3 of them with crutches	Nail breaking (1), Screw penetration into the acetabulum (1), Proximal screw migration (1)	This new operative method corrects and stabilizes severe difficult deformities. The operation is technical demanding requiring a careful ability to manage significant blood loss
Majoor et al[27], 2018	6 (6)	Shepherd's crook deformity	15.7 yr	Corrective osteotomy stabilized by angle blade plate or I.M. nail (1 case), plus grafting in 3 cases	11.2 yr	No significant change of the femoral neck shaft angle	Fractures of the distal part of the plate (2)	PDF deformities can be adequately and safety treated with angled blade plates. Based on literature review, they propose an individualized patient-tailored approach
Fang et al[26], 2018	6 (6)	Shepherd's crook or complex deformity	25.8 yr	Corrective osteotomy stabilized with I.M. nail (PFNA) plus curettage and grafting	3 yr	All patients except one had satisfactory functional and radiologic results	Cut out of the spiral blade (1)	Internal fixation with I.M. nail plus curettage and bone grafting is recommended for treating large lesions with deformity
Wan et al[28], 2019	10 (10)	Shepherd's crook deformity	31.2 yr	Corrective osteotomy stabilized by DHS plate or I.M. nail (3 cases) plus PMMA augmentation in 5 cases	2.8 yr	Correction of coxa vara from 88.1° to 128.5°. Longer operating times and greater blood loss in I.M. nailing	Wound superficial infection (1)	3D printing osteotomy templates facilitate the correction of shepherd's crook deformity. DHS plus PMMA yields excellent results

DHS: Dynamic hip screw; I.M.: Intramedullary; MAS: McCune-Albright syndrome; PFD: Polyostotic fibrous dysplasia; PMMA: Polymethyl methacrylate.