Clinical efficacy of the Ankle Spacer for the treatment of multiple secondary osteochondral lesions of the talus

Table 1 Inclusion and exclusion criteria

Patient	Gender	Age	BMI (kg/m2)	Prior procedures
1	M	36	27	2013: Removal of anterior bony ankle impingement
				2013: Arthroscopic screw fixation of talar osteochondral lesion
				2014: Screw removal
				2015: Hyaluronic acid injections (multiple)
				2016: Arthroscopic Bone Marrow Stimulation for talar osteochondral lesion
2	F	56	23	2005: Spongiosaplasty for talar osteochondral lesion
				2008: Arthroscopic bone marrow stimulation for talar osteochondral lesions
				2014: Retrograde drilling for talar osteochondral lesion
				2017: Hyaluronic acid injections (multiple)

Table 2 Patient characteristics

Inclusion criteria	Exclusion criteria
Age ranging from 18 to 80 yr	Severe ankle malalignment (more than 5° varus or valgus)
Failed previous conservative treatment	Suspicion of grade two or higher (Kellgren-Lawrence-Score) ankle joint degeneration on the tibia side
Complaints for at least 6 mo	Ankle Fracture less than 6 mo ago
Talar osteochondral lesions (multiple degenerative talar cysts present, and/or prior failed operative treatment and/or multiple defects and/or a diameter of 15mm or more)	Tendinitis
	Advanced osteoporosis
	Adiposity grade I (BMI of 30 kg/m2 or more)
	Diabetes mellitus / reumathoid arthritis / severe neuro-arthropathy
	Blood supply limitations and active infections, which may retard healing
	Foreign-body sensitivity
	Currently participating in an investigational drug or another device study that clinically interferes with the current study endpoints

BMI: Body mass index; F: Female; M: Male.

Table 3 Preoperative and postoperative outcomes for patients 1 and 2

Patient 1
Time-Point	FAOS	SF-36	AOFAS ankle hindfoot score	NRS satisfaction with current activity level	NRS satisfaction with daily functioning despite any complaints	NRS satisfaction with treatment so far
Preoperatively	Pain: 56; Symptoms: 46; ADL: 68; Sports: 20 QoL: 25	PCS: 28; MCS: 61	61	3	3	8
3 mo postoperatively	Pain: 86; Symptoms: 82; ADL: 91; Sports: 40 QoL: 63	PCS: 44; MCS: 55	82	7	8	9
6 mo postoperatively	Pain: 79; Symptoms: 86 ; ADL: 93; Sports: 60 QoL: 63	PCS: 45; MCS: 53	75	7	8	9
1 year postoperatively	Pain: 46; Symptoms: 67; ADL: 79; Sports: 25 QoL: 44	PCS: 39; MCS: 56	77	6	4	7
2 years postoperatively	Pain: 62; Symptoms: 81; ADL: 90; Sports: 55 QoL: 69	PCS: 51; MCS: 52	100	8	8	9
Patient 2
Preoperative	Pain: 81; Symptoms: 79; ADL: 91; Sports: N.A. QoL: 25	PCS: 44; MCS: 56	72	5	6	7
3 mo postoperatively	Pain: 64; Symptoms: 68; ADL: 66; Sports: 30 QoL: 0	PCS: 33; MCS: 41	69	2	2	2
6 mo postoperatively	Pain: 68; Symptoms: 69 ; ADL: 72; Sports: 30 QoL: 13	PCS: 29; MCS: 54	71	1	5	1
1 year postoperatively	Pain: 72; Symptoms: 50; ADL: 72; Sports: 30 QoL: 19	PCS: 33; MCS: 51	68	2	5	2
2 years postoperatively	Pain: 81; Symptoms: 68; ADL: 78; Sports: 55 QoL: 50	PCS: 43; MCS: 53	88	9	9	8

ADL: Activities in daily living; AOFAS: American Orthopaedic Foot and Ankle Society; FAOS: Foot and ankle outcome score; MCS: Mental component scale; NRS: Numeric rating scale; PCS: Physical component scale; QoL: Quality of life; SF-36: Short-form 36.

Table 4 Preoperative and postoperative range of motion outcomes patient 1 and 2

	Patient 1		Patient 2
	Dorsiflexion in degrees (affected/unaffected side)	Plantarflexion in degrees (affected/unaffected side)	Dorsiflexion in degrees (affected/unaffected side)	Plantarflexion in degrees (affected/unaffected side)
Preoperative	5 / 10	35 / 40	5 / 5	40 / 40
2 wk postoperatively	5 / 15	20 / 40	2 / 15	25 / 40
6 wk postoperatively	7 / 10	35 / 40	5 / 10	35 / 40
3 mo postoperatively	10 / 10	35 / 45	5 / 10	35 / 40
6 mo postoperatively	10 / 10	35 / 45	10 / 10	35 / 40
1 yr postoperatively	10 / 10	35 / 45	10 / 10	35 / 40
2 yr postoperatively	10 / 10	35 / 45	7 / 10	35 / 40