Table 1 Summary of the major series present in the literature

De Meulemeester et al. [8]

Case report

61

60

None

Evaluation of pain and need for aids

The patient walked without pain and without the need for any support

Nieder et al. [10]

76

32–84

12–74

15 infections;

4 malpositions of the saddle;

4 dislocations;

2 fractures;

2 cases of femoral loosening

MSTS

The various parameters were reported separately and were not combined into a total score. The authors concluded that unsatisfactory results could be related to the rigid nature of the system, but that the saddle prosthesis can be used as a salvage procedure

Van der Lei et al. [11]

2 cases reported

Patient 1:68

Patient 2:43

Patient 2: 30 months

None

Evaluation of pain and need for aids

Patient 1 died 9 months after surgery. Patient 2 walked without pain and without the need for any support

Aboulafia et. al. [6]

17

59

33

3 local wound complications;

2 prosthetic dissociations;

2 dislocations;

1 secondary fracture;

1 partial sciatic nerve laceration

MSTS

9 patients were available for functional evaluation at follow-up:

7 patients showed excellent function (17–20 points in Enneking system of functional evaluation)

2 patients showed good function (14–15 points)

Windhager [12]

4

41

34

1 femoral palsy;

1 infection

MSTS

1 patient: good

2 patients: fair

1 patient: poor

The mean MSTS score was 12.2 out of 30

Renard et al. [3]

15

48

36

4 deep infections;

3 fractures;

5 cases of heterotopic ossification

MSTS

Satisfactory short-term functional results. The mean MSTS score at 6 months was 50 % (no further detailed score figures are reported)

Cottias et al. [2]

17

44

42

3 infections;

2 mechanical failures;

2 sacroiliac subluxations;

4 migrations of the saddle;

3 dislocations;

3 cases of nerve damage

MSTS

TESS

9 patients were available for functional evaluation at follow-up:

The mean MSTS score was 57 %

The mean TESS score was 58 points (range: 39–95 points)

Natarajan et al. [9]

6

37

30

1 deep infection;

1 vascular thrombosis

MSTS

3 patients: excellent

2 patients: good

1 patient: poor

(No further detailed score figures are reported)

Benevenia et al. [1]

20

61

20

2 dislocations;

1 hematoma and wound necrosis

MSTS

The mean MSTS score was 55 %

(No further detailed score figures are reported)

Aljassir et al. [4]

27

53

45

10 infections;

10 cases of heterotopic ossification;

6 dislocations;

6 fractures;

5 nerve palsies

MSTS

TESS

14 patients were available for functional evaluation at follow-up:

The mean MSTS 93 score was 50.8 %

The mean MSTS 87 score was 15.3 %

The mean TESS score was 64.4 %